@article{11755, abstract = {Hyperlink analysis algorithms significantly improve the relevance of the search results on the Web, so much so that all major Web search engines claim to use some type of hyperlink analysis. However, the search engines do not disclose details about the type of hyperlink analysis they perform, mostly to avoid manipulation of search results by Web-positioning companies. The article discusses how hyperlink analysis can be applied to ranking algorithms, and surveys other ways Web search engines can use this analysis.}, author = {Henzinger, Monika H}, issn = {1941-0131}, journal = {IEEE Internet Computing}, number = {1}, pages = {45--50}, publisher = {Institute of Electrical and Electronics Engineers}, title = {{Hyperlink analysis for the Web}}, doi = {10.1109/4236.895141}, volume = {5}, year = {2001}, } @article{11892, abstract = {We present the first fully dynamic algorithm for maintaining a minimum spanning forest in time 𝑜(𝑛√) per operation. To be precise, the algorithm uses O(n1/3 log n) amortized time per update operation. The algorithm is fairly simple and deterministic. An immediate consequence is the first fully dynamic deterministic algorithm for maintaining connectivity and bipartiteness in amortized time O(n1/3 log n) per update, with O(1) worst case time per query.}, author = {Henzinger, Monika H and King, Valerie}, issn = {1095-7111}, journal = {SIAM Journal on Computing}, number = {2}, pages = {364--374}, publisher = {Society for Industrial & Applied Mathematics}, title = {{Maintaining minimum spanning forests in dynamic graphs}}, doi = {10.1137/s0097539797327209}, volume = {31}, year = {2001}, } @inproceedings{11914, abstract = {Previous studies of the Web graph structure have focused on the graph structure at the level of individual pages. In actuality the Web is a hierarchically nested graph, with domains, hosts and Web sites introducing intermediate levels of affiliation and administrative control. To better understand the growth of the Web we need to understand its macro-structure, in terms of the linkage between Web sites. We approximate this by studying the graph of the linkage between hosts on the Web. This was done based on snapshots of the Web taken by Google in Oct 1999, Aug 2000 and Jun 2001. The connectivity between hosts is represented by a directed graph, with hosts as nodes and weighted edges representing the count of hyperlinks between pages on the corresponding hosts. We demonstrate how such a "hostgraph" can be used to study connectivity properties of hosts and domains over time, and discuss a modified "copy model" to explain observed link weight distributions as a function of subgraph size. We discuss changes in the Web over time in the size and connectivity of Web sites and country domains. We also describe a data mining application of the hostgraph: a related host finding algorithm which achieves a precision of 0.65 at rank 3.}, author = {Bharat, K. and Chang, Bay-Wei and Henzinger, Monika H and Ruhl, M.}, booktitle = {1st IEEE International Conference on Data Mining}, isbn = {0-7695-1119-8}, issn = {15504786}, location = {San Jose, CA, United States}, pages = {51--58}, publisher = {Institute of Electrical and Electronics Engineers}, title = {{Who links to whom: Mining linkage between Web sites}}, doi = {10.1109/ICDM.2001.989500}, year = {2001}, } @inbook{2709, author = {Erdös, LĂĄszlĂł}, booktitle = {13th International Congress of Mathematical Physics}, isbn = {9781571460851}, pages = {273 -- 281}, publisher = { International Press of Boston}, title = {{Long time dynamics of an electron in a weakly coupled phonon field}}, year = {2001}, } @article{2734, abstract = {In this paper we describe an intrinsically geometric way of producing magnetic fields on S3 and R3 for which the corresponding Dirac operators have a non-trivial kernel. In many cases we are able to compute the dimension of the kernel. In particular we can give examples where the kernel has any given dimension. This generalizes the examples of Loss and Yau [1].}, author = {Erdös, LĂĄszlĂł and Solovej, Jan}, issn = {0129-055X}, journal = {Reviews in Mathematical Physics}, number = {10}, pages = {1247 -- 1280}, publisher = {World Scientific Publishing}, title = {{The kernel of Dirac operators on S3 and R3}}, doi = {10.1142/S0129055X01000983}, volume = {13}, year = {2001}, } @article{2735, abstract = {We establish the exact low-energy asymptotics of the integrated density of states (Lifschitz tail) in a homogeneous magnetic field and Poissonian impurities with a repulsive single-site potential of Gaussian decay. It has been known that the Gaussian potential tail discriminates between the so-called “classical” and “quantum” regimes, and precise asymptotics are known in these cases. For the borderline case, the coexistence of the classical and quantum regimes was conjectured. Here we settle this last remaining open case to complete the full picture of the magnetic Lifschitz tails.}, author = {Erdös, LĂĄszlĂł}, issn = {0044-3719}, journal = {Probability Theory and Related Fields}, number = {2}, pages = {219 -- 236}, publisher = {Springer}, title = {{Lifschitz tail in a magnetic field: Coexistence of classical and quantum behavior in the borderline case}}, doi = {10.1007/PL00008803}, volume = {121}, year = {2001}, } @article{2736, abstract = {We consider the time evolution of N bosonic particles interacting via a mean field Coulomb potential. Suppose the initial state is a product wavefunction. We show that at any finite time the correlation functions factorize in the limit N → ∞. Furthermore, the limiting one particle density matrix satisfies the nonlinear Hartree equation. The key ingredients are the uniqueness of the BBGKY hierarchy for the correlation functions and a new apriori estimate for the many-body Schrödinger equations.}, author = {Erdös, LĂĄszlĂł and Yau, Horng}, issn = {1095-0761}, journal = {Advances in Theoretical and Mathematical Physics}, number = {6}, pages = {1169 -- 1205}, publisher = {International Press}, title = {{Derivation of the nonlinear Schrödinger equation from a many body Coulomb system}}, doi = {10.48550/arXiv.math-ph/0111042}, volume = {5}, year = {2001}, } @article{2981, abstract = {Plants contain a novel unique subfamily of Rho GTPases, vital components of cellular signalling networks. Here we report a general role for some members of this family in polarized plant growth processes. We show that Arabidopsis AtRop4 and AtRop6 encode functional GTPases with similar intrinsic GTP hydrolysis rates. We localized AtRop proteins in root meristem cells to the cross-wall and cell plate membranes. Polar localization of AtRops in trichoblasts specifies the growth sites for emerging root hairs. These sites were visible before budding and elongation of the Arabidopsis root hair when AtRops accumulated at their tips. Expression of constitutively active AtRop4 and AtRop6 mutant proteins in root hairs of transgenic Arabidopsis plants abolished polarized growth and delocalized the tip-focused Ca2+ gradient. Polar localization of AtRops was inhibited by brefeldin A, but not by other drugs such as latrunculin B, cytochalasin D or caffeine. Our results demonstrate a general function of AtRop GTPases in tip growth and in polar diffuse growth.}, author = {Molendijk, Arthur and Bischoff, Friedrich and Rajendrakumar, Chadalavada and Friml, JirĂ­ and Braun, Markus and Gilroy, Simon and Palme, Klaus}, issn = {0261-4189}, journal = {EMBO Journal}, number = {11}, pages = {2779 -- 2788}, publisher = {Wiley-Blackwell}, title = {{Arabidopsis thaliana Rop GTPases are localized to tips of root hairs and control polar growth}}, doi = {10.1093/emboj/20.11.2779}, volume = {20}, year = {2001}, } @article{2982, abstract = {Polar auxin transport is crucial for the regulation of auxin action and required for some light-regulated responses during plant development. We have found that two mutants of Arabidopsis - doc1, which displays altered expression of light-regulated genes, and tir3, known for its reduced auxin transport - have similar defects and define mutations in a single gene that we have renamed BIG. BIG is very similar to the Drosophila gene Calossin/Pushover, a member of a gene family also present in Caenorhabditis elegans and human genomes. The protein encoded by BIG is extraordinary in size, 560 kD, and contains several putative Zn-finger domains. Expression-profiling experiments indicate that altered expression of multiple light-regulated genes in doc1 mutants can be suppressed by elevated levels of auxin caused by overexpression of an auxin biosynthetic gene, suggesting that normal auxin distribution is required to maintain low-level expression of these genes in the dark. Double mutants of tir3 with the auxin mutants pin1, pid, and axr1 display severe defects in auxin-dependent growth of the inflorescence. Chemical inhibitors of auxin transport change the intracellular localization of the auxin efflux carrier PIN1 in doc1/tir3 mutants, supporting the idea that BIG is required for normal auxin efflux.}, author = {Gil, Pedro and Dewey, Elizabeth and Friml, JirĂ­ and Zhao, Yunde and Snowden, Kimberley and Putterill, Jo and Palme, Klaus and Estelle, Mark and Chory, Joanne}, issn = {0890-9369}, journal = {Genes and Development}, number = {15}, pages = {1985 -- 1997}, publisher = {Cold Spring Harbor Laboratory Press}, title = {{BIG: A calossin-like protein required for polar auxin transport in Arabidopsis}}, doi = {10.1101/gad.905201}, volume = {15}, year = {2001}, } @article{2983, abstract = {Polar transport of the phytohormone auxin mediates various processes in plant growth and development, such as apical dominance, tropisms, vascular patterning and axis formation. This view is based largely on the effects of polar auxin transport inhibitors. These compounds disrupt auxin efflux from the cell but their mode of action is unknown. It is thought that polar auxin flux is caused by the asymmetric distribution of efflux carriers acting at the plasma membrane. The polar localization of efflux carrier candidate PIN1 supports this model. Here we show that the seemingly static localization of PIN1 results from rapid actin-dependent cycling between the plasma membrane and endosomal compartments. Auxin transport inhibitors block PIN1 cycling and inhibit trafficking of membrane proteins that are unrelated to auxin transport. Our data suggest that PIN1 cycling is of central importance for auxin transport and that auxin transport inhibitors affect efflux by generally interfering with membrane-trafficking processes. In support of our conclusion, the vesicle-trafficking inhibitor brefeldin A mimics physiological effects of auxin transport inhibitors.}, author = {Geldner, Niko and Friml, JirĂ­ and Stierhof, York and JĂŒrgens, Gerd and Palme, Klaus}, issn = {0028-0836}, journal = {Nature}, number = {6854}, pages = {425 -- 428}, publisher = {Nature Publishing Group}, title = {{Auxin transport inhibitors block PIN1 cycling and vesicle trafficking}}, doi = {10.1038/35096571}, volume = {413}, year = {2001}, } @article{2984, abstract = {Auxins represent an important class of plant hormone that regulate plant development. Plants use specialized carrier proteins to transport the auxin indole-3-acetic acid (IAA) to target tissues. To date, efflux carrier-mediated polar auxin transport has been assumed to represent the sole mode of long distance IAA movement. Localization of the auxin permease AUX1 in the Arabidopsis root apex has revealed a novel phloem-based IAA transport pathway. AUX1, asymmetrically localized to the plasma membrane of root protophloem cells, is proposed to promote the acropetal, post-phloem movement of auxin to the root apex. MS analysis shows that IAA accumulation in aux1 mutant root apices is impaired, consistent with an AUX1 phloem unloading function. AUX1 localization to columella and lateral root cap tissues of the Arabidopsis root apex reveals that the auxin permease regulates a second IAA transport pathway. Expression studies using an auxin-regulated reporter suggest that AUX1 is necessary for root gravitropism by facilitating basipetal auxin transport to distal elongation zone tissues.}, author = {Swarup, Ranjan and Friml, JirĂ­ and Marchant, Alan and Ljung, Karin and Sandberg, Göran and Palme, Klaus and Bennett, Malcolm}, issn = {Genes and Development}, journal = {Genes and Development}, number = {20}, pages = {2648 -- 2653}, publisher = {Cold Spring Harbor Laboratory Press}, title = {{Localization of the auxin permease AUX1 suggests two functionally distinct hormone transport pathways operate in the Arabidopsis root apex}}, doi = {10.1101/gad.210501}, volume = {15}, year = {2001}, } @article{2985, abstract = {The elimination voltammetry with linear scan (EVLS) was used to study adenine and cytosine reduction signals at the mercury electrode. In comparison with the linear scan voltammetry (which provides only one unresolved peak), two elimination functions provide good resolution of individual peaks and significant increase of sensitivity. The first elimination function eliminates the kinetic current (Ik) and conserves the diffusion current (Id). The second elimination function eliminates kinetic and charging currents (Ik and Ic) simultaneously and conserves the diffusion current (Id). Both functions give two well-resolved peaks of adenine and cytosine in a wide concentration range, while the linear sweep voltammetry gives badly resolved peaks due to hydrogen evolution. The best resolution of peaks is observed in acetate buffer at pH 3.8 and the detection limit for both substances is 500 nM. The concentration dependence of EVLS peak heights for one substance at the constant concentration of the other substance is linear. The peak potentials differ in these elimination functions. The difference in EVLS peak potentials gives the possibility to evaluate αna. Elimination voltammetry with linear scan contributes to the resolution of cathodic signals of purine and pyrimidine bases at very negative potentials near supporting electrolyte discharge. Copyright © 2001 Elsevier Science B.V.}, author = {TrnkovĂĄ, LibuĆĄe and Friml, JirĂ­ and Dračka, Oldƙich}, isbn = {1567-5394}, journal = {Bioelectrochemistry}, number = {2}, pages = {131 -- 136}, publisher = {Elsevier}, title = {{Elimination voltammetry of adenine and cytosine mixtures}}, doi = {10.1016/S1567-5394(01)00119-0}, volume = {54}, year = {2001}, } @inproceedings{3169, abstract = {Several new algorithms for visual correspondence based on graph cuts [7, 14, 17] have recently been developed. While these methods give very strong results in practice, they do not handle occlusions properly. Specifically, they treat the two input images asymmetrically, and they do not ensure that a pixel corresponds to at most one pixel in the other image. In this paper, we present a new method which properly addresses occlusions, while preserving the advantages of graph cut algorithms. We give experimental results for stereo as well as motion, which demonstrate that our method performs well both at detecting occlusions and computing disparities.}, author = {Kolmogorov, Vladimir and Zabih, Ramin}, booktitle = {Proceedings of the 8th IEEE International Conference on Computer Vision}, isbn = {0769511430}, location = {Vancouver, Canada}, pages = {508 -- 515}, publisher = {IEEE}, title = {{Computing visual correspondence with occlusions using graph cuts}}, doi = {10.1109/ICCV.2001.937668}, volume = {2}, year = {2001}, } @article{1452, abstract = {In this Note we present pairs of hyperkĂ€hler orbifolds which satisfy two different versions of mirror symmetry. On the one hand, we show that their Hodge numbers (or more precisely, stringy E-polynomials) are equal. On the other hand, we show that they satisfy the prescription of Strominger, Yau, and Zaslow (which in the present case goes back to Bershadsky, Johansen, Sadov and Vafa): that a Calabi-Yau and its mirror should fiber over the same real manifold, with special Lagrangian fibers which are tori dual to each other. Our examples arise as moduli spaces of local systems on a curve with structure group SL(n); the mirror is the corresponding space with structure group PGL(n). The special Lagrangian tori come from an algebraically completely integrable Hamiltonian system: the Hitchin system.}, author = {Hausel, Tamas and Thaddeus, Michael}, issn = {0764-4442}, journal = {Comptes Rendus de l'Academie des Sciences - Series I: Mathematics}, number = {4}, pages = {313 -- 318}, publisher = {Elsevier}, title = {{Examples of mirror partners arising from integrable systems}}, doi = {10.1016/S0764-4442(01)02057-2}, volume = {333}, year = {2001}, } @article{1453, abstract = {In this Letter we exhibit a one-parameter family of new Taub-NUT instantons parameterized by a half-line. The endpoint of the half-line will be the reducible Yang-Mills instanton corresponding to the Eguchi-Hanson-Gibbons L2 harmonic 2-form, while at an inner point we recover the Pope-Yuille instanton constructed as a projection of the Levi-CivitĂĄ connection onto the positive su(2)+ ⊂ so(4) subalgebra. Our method imitates the Jackiw-Nohl-Rebbi construction originally designed for flat R4. That is we find a one-parameter family of harmonic functions on the Taub-NUT space with a point singularity, rescale the metric and project the obtained Levi-CivitĂĄ connection onto the other negative su(2)- ⊂ so(4) part. Our solutions will possess the full U(2) symmetry, and thus provide more solutions to the recently proposed U(2) symmetric ansatz of Kim and Yoon.}, author = {Etesi, GĂĄbor and Hausel, Tamas}, issn = {0370-2693}, journal = {Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics}, number = {1-2}, pages = {189 -- 199}, publisher = {Elsevier}, title = {{Geometric construction of new Yang-Mills instantons over Taub-NUT space}}, doi = {10.1016/S0370-2693(01)00821-8}, volume = {514}, year = {2001}, } @article{1454, abstract = {We address the problem of finding Abelian instantons of finite energy on the Euclidean Schwarzschild manifold. This amounts to construct self-dual L2 harmonic 2-forms on the space. Gibbons found a non-topological L2 harmonic form in the Taub-NUT metric, leading to Abelian instantons with continuous energy. We imitate his construction in the case of the Euclidean Schwarzschild manifold and find a non-topological self-dual L2 harmonic 2-form on it. We show how this gives rise to Abelian instantons and identify them with SU(2)-instantons of Pontryagin number 2n2 found by Charap and Duff in 1977. Using results of Dodziuk and Hitchin we also calculate the full L2 harmonic space for the Euclidean Schwarzschild manifold.}, author = {Etesi, GĂĄbor and Hausel, Tamas}, issn = {0393-0440}, journal = {Journal of Geometry and Physics}, number = {1-2}, pages = {126 -- 136}, publisher = {Elsevier}, title = {{Geometric interpretation of Schwarzschild instantons}}, doi = {10.1016/S0393-0440(00)00040-1}, volume = {37}, year = {2001}, } @article{17816, abstract = {The lifetime of the luminous phase of quasars is constrained by current observations to be 10^6 â‰Č tQ â‰Č 10^8 yr but is otherwise unknown. We model the quasar luminosity function in detail in the optical and X-ray bands using the Press-Schechter formalism and show that the expected clustering of quasars depends strongly on their assumed lifetime tQ. We quantify this dependence and find that existing measurements of the correlation length of quasars are consistent with the range 10^6 â‰Č tQ â‰Č 10^8 yr. We then show that future measurements of the power spectrum of quasars out to z ~ 3, from the Anglo-Australian Telescope Two-Degree Field or Sloan Digital Sky Survey, can significantly improve this constraint and in principle allow a precise determination of tQ. We estimate the systematic errors introduced by uncertainties in the modeling of the quasar-halo relationship, as well as by the possible existence of obscured quasars.}, author = {Haiman, ZoltĂĄn and Hui, Lam}, issn = {1538-4357}, journal = {The Astrophysical Journal}, number = {1}, pages = {27--38}, publisher = {American Astronomical Society}, title = {{Constraining the lifetime of quasars from their spatial clustering}}, doi = {10.1086/318330}, volume = {547}, year = {2001}, } @article{17824, abstract = {The ubiquity of supermassive black holes (SMBHs) at the centers of nearby luminous galaxies can arise from the multiple mergers experienced by dark matter halos in hierarchical structure formation models, even if only a small fraction of these galaxies harbor SMBHs at high redshifts. We illustrate this possibility using cosmological Monte Carlo simulations of the merger history of dark matter halos and their associated SMBHs. In our most extreme models, in order to populate nearly every bright galaxy with an SMBH at z = 0, only a few percent of the halos with virial temperatures above 104 K are required to harbor an SMBH at high redshift. This possibility must be included in studies of the luminosity function and the clustering properties of quasars. We predict the number of SMBH merger events that are detectable by the gravitational wave experiment Laser Interferometer Space Antenna (LISA), as a function of redshift, out to z = 5. Although the event rates can be significantly reduced in scenarios with rare SMBHs, a minimum of ~10 detectable merger events per year is predicted if SMBH binaries coalesce efficiently. The observed distribution of events with redshift could yield valuable information on the SMBH formation process. If SMBH binaries do not coalesce, we find that at least several SMBH slingshot ejections probably occurred from z = 5 to the present in each galaxy more massive than ~1011 M☉ at z = 0. Although our results are sensitive to the minimum cooling mass assumed for the formation of SMBHs, we expect the qualitative predictions of our models to be robust.}, author = {Menou, Kristen and Haiman, ZoltĂĄn and Narayanan, Vijay K.}, issn = {1538-4357}, journal = {The Astrophysical Journal}, number = {2}, pages = {535--542}, publisher = {American Astronomical Society}, title = {{The merger history of supermassive black holes in galaxies}}, doi = {10.1086/322310}, volume = {558}, year = {2001}, } @article{17825, abstract = {We present the results from a survey of i-dropout objects selected from ∌1550 deg^2 of multicolor imaging data from the Sloan Digital Sky Survey to search for luminous quasars at z ≳ 5.8. Objects with i*-z* > 2.2 and z* < 20.2 are selected, and follow-up J-band photometry is used to separate L- and T-type cool dwarfs from high-redshift quasars. We describe the discovery of three new quasars, SDSSp J083643.85+005453.3 (z = 5.82), J130608.26+035626.3 (z = 5.99), and J103027.10+052455.0 (z = 6.28). The quasar SDSSp J083643.85+005453.3 is a radio source with flux of 1.1 mJy at 20 cm. The spectra of all three quasars show strong and broad Lyα + N V emission lines and very strong Lyα forest absorption, with a mean continuum decrement DA > 0.90. The ARC 3.5 m spectrum of SDSSp J103027.10+052455.0 shows that over a range of ∌300 Å immediately blueward of the Lyα emission, the average transmitted flux is only 0.003 ± 0.020 times that of the continuum level, consistent with zero flux over a ∌300 Å range of the Lyα forest region and suggesting a tentative detection of the complete Gunn-Peterson trough. The existence of strong metal lines in the quasar spectra suggests early metal enrichment in the quasar environment. The three new objects, together with the previously published z = 5.8 quasar SDSSp J104433.04-012502.2, form a complete color-selected flux-limited sample at z ≳ 5.8. We estimate the selection function of this sample, taking into account the estimated variations in the quasar spectral energy distribution, as well as observational photometric errors. We find that at z = 6, the comoving density of luminous quasars at M1450 < -26.8 (H0 = 50 km s-1 Mpc-1, Ω = 1) is 1.1 × 10-9 Mpc-3. This is a factor of ∌2 lower than that at z ∌ 5 and is consistent with an extrapolation of the observed quasar evolution at z < 5. Using the current sample, we discuss the constraint on the shape of the quasar luminosity function and the implications for the contribution of quasars to the ionizing background at z ∌ 6. The luminous quasars discussed in the paper have central black hole masses of several times 109 M⊙ by the Eddington argument, with likely dark halo masses on the order of 1013 M⊙. Their observed space density provides a sensitive test of models of quasar and galaxy formation at high redshift.}, author = {Fan, Xiaohui and Narayanan, Vijay K. and Lupton, Robert H. and Strauss, Michael A. and Knapp, Gillian R. and Becker, Robert H. and White, Richard L. and Pentericci, Laura and Leggett, S. K. and Haiman, ZoltĂĄn and Gunn, James E. and Ivezić, Ćœeljko and Schneider, Donald P. and Anderson, Scott F. and Brinkmann, J. and Bahcall, Neta A. and Connolly, Andrew J. and Csabai, IstvĂĄn and Doi, Mamoru and Fukugita, Masataka and Geballe, Tom and Grebel, Eva K. and Harbeck, Daniel and Hennessy, Gregory and Lamb, Don Q. and Miknaitis, Gajus and Munn, Jeffrey A. and Nichol, Robert and Okamura, Sadanori and Pier, Jeffrey R. and Prada, Francisco and Richards, Gordon T. and Szalay, Alex and York, Donald G.}, issn = {0004-6256}, journal = {The Astronomical Journal}, number = {6}, pages = {2833--2849}, publisher = {American Astronomical Society}, title = {{A survey of z > 5.8 quasars in the sloan digital sky survey. I. Discovery of three new quasars and the spatial density of luminous quasars at z ∌ 6}}, doi = {10.1086/324111}, volume = {122}, year = {2001}, } @article{17826, abstract = {The hardness of the ionizing continuum from the first sources of UV radiation plays a crucial role in the reionization of the intergalactic medium (IGM). While usual stellar populations have soft spectra, miniquasars or metal-free stars with high effective temperatures may emit hard photons, capable of doubly ionizing helium and increasing the IGM temperature. Absorption within the source and in the intervening IGM will render the ionizing continuum of high-redshift sources inaccessible to direct observation. Here we show that He recombination lines from the first luminous objects are potentially detectable by the Next Generation Space Telescope. Together with measurements of the Hα emission line, this detection can be used to infer the ratio of He II to H I ionizing photons, [mathematical formula]. A measurement of this ratio would shed light on the nature and emission mechanism of the first luminous sources, with important astrophysical consequences for the reheating and reionization of the IGM.}, author = {Oh, S. Peng and Haiman, ZoltĂĄn and Rees, Martin J.}, issn = {1538-4357}, journal = {The Astrophysical Journal}, number = {1}, pages = {73--77}, publisher = {American Astronomical Society}, title = {{He II recombination lines from the first luminous objects}}, doi = {10.1086/320650}, volume = {553}, year = {2001}, }