Arslan, Gökhan, et al. “Trend Analysis and Forecasting of the Gökırmak River Streamflow (Turkey)”. Oceanological and Hydrobiological Studies, vol. 49, no. 3, Sept. 2020, pp. 230-46, https://czasopisma.bg.ug.edu.pl/index.php/oandhs/article/view/7779.