Evolution and modern state of lakes of Southern Ural / V. I. Khomutova, M. A. Andreeva, N. N. Davydova [et. al.] // Fundamental and applied problems of environmental protection. Vol. 4 : International conference, September, 12-16, 1995, Tomsk : abstracts. Tomsk, 1995. Vol. 4 : Contemporary problems of geoecology and rational use of natural resources ; Ecological aspects of urban design and agrilandscape formation. Recreational use of nature. P. 29-30