1. Baranov, V. K. (1965b). “FOCON” (in Russian). Russian certificate of authorship 167327, specification published March 18, 1965.
2. Baranov, V. K. (1967). “Device for Restricting in One Plane the Angular Aperture of a Pencil of Rays from a Light Source” (in Russian). Russian certificate of authorship 200530, specification published October 31, 1967.
3. Study of the illumination characteristics of hollow focons;Baranov;Sov. J. Opt. Technol.,1966