Kochanowicz, Marcin, Wojciech Mazerski, Jacek Żmojda, K. Czajkowski, and Dominik Dorosz. “Green Upconversion Emission in Tellurite Optical Fibre Codoped With Yb3+ Er3+”. Photonics Letters of Poland 5, no. 1 (March 28, 2013): pp. 35–37. Accessed April 26, 2024. https://photonics.pl/PLP/index.php/letters/article/view/5-13.