Nigiyan, S.A. “ON $\lambda$-DEFINABILITY OF ARITHMETICAL FUNCTIONS WITH INDETERMINATE VALUES OF ARGUMENTS”. Proceedings of the YSU A: Physical and Mathematical Sciences 50, no. 2 (240) (June 6, 2016): 39–47. Accessed May 17, 2024. https://journals.ysu.am/index.php/proceedings-phys-math/article/view/vol50_no2_2016_pp039-047.