(1)
S. Gredeskul, Y. Avishai, and M. Ya. Ya, Electron in a magnetic field and two-dimensional point potentials: To the memory of I. M. Lifshits, Low Temp. Phys. 23, 15–26, (1997) [Fiz. Nizk. Temp. 23, 21-35, (1997)] DOI: https://doi.org/10.1063/1.593330.