Observation of an autumn accumulation of Black Storks in Sumy region. - N.P. Knysh, N.M. Tverdokhleb. - Berkut. 16 (1). 2007. - P. 130.
30 birds were found on a meadow on 15.09.2007. This flock has appeared here on 1.09 and did not change its location. [Russian].