1. Akhverdyan, M.R, Cytogenetics and taxonomy of closely related and sibling species of voles of the fauna of the Transcaucasia, Extended Abstract of Cand. Sci. (Biol.) Dissertation, Moscow: IEMEZh RAN, 1989.
2. Akhverdyan, M.R., Lyapunova, E.A., and Vorontsov, N.N, New data on the karyology of Pitymys of the Caucasus, in Gryzuny. Tezisy dokl. VII Vses. soveshch. (Rodents: Abstr. VII All-Union. Conf.), Sverdlovsk: Ural. otd. AN SSSR, 1988, vol. 1, pp. 58–60.
3. Akhverdyan, M.R., Lyapunova, E.A., and Vorontsov, N.N, Karyology and taxonomy of pine voles of the Caucasus and Transcaucasia (Terricola, Arvicolinae, Rodentia), Zool. Zh., 1992, vol. 71, no. 3, pp. 96–110.
4. Akhverdyan, M.R., Lyapunova, E.A., and Vorontsov, N.N., A rare case of chromosomal mutations in pine voles Terricola majori (Arvicolinae, Rodentia), Genetika, 1997, vol. 33, no. 6, pp. 852–854.
5. Baskevich, M.I, Comparative analysis of the characteristics of sperm and karyotypes in three species of pine voles: Terricola majori, T. daghestanicus, and T. subterraneus (Rodentia, Cricetidae) from the territory of the former USSR, Zool. Zh., 1997, vol. 76, no. 5, pp. 597–607.