Erdös, László. “On Some Problems of P. Turán Concerning Power Sums of Complex Numbers.”https://doi.org/10.1007/BF00052086__Acta Mathematica Hungarica. Springer, 1992.https://doi.org/10.1007/BF00052086 .
LibreCat: https://research-explorer.ista.ac.at/record/2714
DOI: 10.1007/BF00052086