%0 Journal Article %A Yu. V. Karakashian %T Excitons in semiconductors with narrow forbidden zone %J Proceedings of the Yerevan State University. Physical and mathematical sciences %D 1989 %P 144-147 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/UZERU_1989_1_a12/ %G ru %F UZERU_1989_1_a12