Kurbatska, I., A. Alsevska, L. Gegere, and V. Bobrovs. “Investigation of Influence of Mixed Configurations on Performance of WDM-PON”. Elektronika Ir Elektrotechnika, vol. 23, no. 2, Apr. 2017, pp. 74-78, doi:10.5755/j01.eie.23.2.18003.