2019. INVESTIGATIONS OF FORMATION OF PHYTOPLANKTON COMMUNITY IN THE ARPA RIVER (ARMENIA) AND ITS MAIN TRIBUTARIES. Proceedings of the YSU B: Chemical and Biological Sciences. 53, 1 (248) (Apr. 2019), 46–52. DOI:https://doi.org/10.46991/PYSUB.2019.53.1.046.