1. I. Gregora, B. Velický, M. Zavetova
    Refractive index of crystalline and amorphous GeS
    phys. status solidi b 104 (1981) K95
  2. J. Mašek, B. Velický
    Electronic states in amorphous germanium chalcogenides
    J. Physique 42, Suppl. 10 (1981) C4-133
  3. V. Szocs, V. Capek, B. Velický
    Simple two-band s-d model for ferromagnetic semiconductors with hybridization II. Further development and optical properties
    phys. status solidi b 103 (1981) 139