Romanenko В.І., Romanenko О.В., and Yatsenko Л.П. “Analog of the Coherent Population Trapping State in a Polychromatic Field”. Ukrainian Journal of Physics 56, no. 10 (February 6, 2022): 975. Accessed May 12, 2024. https://ujp.bitp.kiev.ua/index.php/ujp/article/view/2021457.