Mikailov Khidir Mustafa, Mammadov Ruslan Tavakkul, Rustamov Bayram Nizam, and Rustamova Aysel Bayram. “Spectral Variability of the Symbiotic Star CH Cyg”. Proceedings of the Pakistan Academy of Sciences: A. Physical and Computational Sciences 60, no. 1 (March 15, 2023): 9–13. Accessed November 10, 2024. https://ppaspk.org/index.php/PPAS-A/article/view/806.