1. Alekseev, M. Voprosy Sravnitel’no-Istoricheskoy Grammatiki Lezginskikh Iazykov. Morfologiia. Sintaksis [Issues of the Comparative and Historical Grammar of Lezgian Languages. Morphology. Syntax]. Moscow: Nauka, 1985. 157 p.
2. Andronov, M. Dravidian Languages. Moscow: Nauka, 1970. 199 p.
3. Armstrong, R.G. Yoruba Numerals. Oxford: Oxford University Press, 1962. 36 p.
4. Atkins, G. Notes on the concords and classes of Bantu numerals. African Language Studies, 1961, 2. P. 42–48.
5. Aulie, W. High-layered numerals in Chol (Mayan). International Journal of American Linguistics, 1957, vol. 23, no. 4. P. 281– 283.