Savel'ev S I

Publications in Math-Net.Ru

1. On surfaces with planar generators along which the tangent plane is constant
   
   Izv. Vyssh. Uchebn. Zaved. Mat., 1960, no. 2,  154–167
2. Surfaces with plane generatrices along which the tangent plane is constant
   
   Dokl. Akad. Nauk SSSR, 115:4 (1957),  663–665