Under ice density and mobility of fish in winter-seining area of two Finnish lakes as revealed by echo-surveyJuha Jurvelius, Juha Lilja, Esa Hirvonen, Raimo Riikonen and Timo J. MarjomäkiAquat. Living Resour., 13 5 (2000) 403-408DOI: https://doi.org/10.1016/S0990-7440(00)01061-5
