Sizhuk, A., and S. Yezhov. “Application of the Generalized Absorptance for Accounting the Recoil and Doppler Effects”. Ukrainian Journal of Physics 62, no. 4 (December 15, 2018): 299. Accessed July 14, 2020. https://ujp.bitp.kiev.ua/index.php/ujp/article/view/2018688.