M. A. Efremov, S. V. Petropavlovsky, M. V. Fedorov, W. P. Schleich, V. P. Yakovlev, “Formation of two-dimensional nonspreading atomic wave packets in the field of two standing light waves”, Kvantovaya Elektronika, 35:8 (2005), 675–678 [Quantum Electron., 35:8 (2005), 675–678]
