Ragiń, T., Baranowska, A., Sołtys, M., Górny, A., Zmojda, J., Kochanowicz, M., … Dorosz, D. (2018). Up-conversion luminescence in low phonon heavy metal oxide glass co-doped with Er3+/Ho3+. Photonics Letters of Poland, 10(1), 2–4. https://doi.org/10.4302/plp.v10i1.802