Akopyan, Arseniy, et al. “On the Circle Covering Theorem by A.W. Goodman and R.E. Goodman.”10.1007/s00454-017-9883-x__Discrete &; Computational Geometry, vol. 59, no. 4, Springer, 2018, pp. 1001–09, doi:10.1007/s00454-017-9883-x.

Burton, Benjamin, et al. “Finding Non-Orientable Surfaces in 3-Manifolds.”10.1007/s00454-017-9900-0__Discrete &; Computational Geometry, vol. 58, no. 4, Springer, 2017, pp. 871–88, doi:10.1007/s00454-017-9900-0.

cadek, Martin, et al. “Algorithmic Solvability of the Lifting Extension Problem.”10.1007/s00454-016-9855-6__Discrete &; Computational Geometry, vol. 54, no. 4, Springer, 2017, pp. 915–65, doi:10.1007/s00454-016-9855-6.