Litvin F L

Publications in Math-Net.Ru

1. A sufficient criterion for the existence of an envelope of characteristics and a cuspidal edge on the enveloping surface of a parametrized family of surfaces
   
   Izv. Vyssh. Uchebn. Zaved. Mat., 1977, no. 3,  20–23
2. Determination of the enveloping lines of contact of mutually enveloped surfaces
   
   Izv. Vyssh. Uchebn. Zaved. Mat., 1975, no. 10,  47–50