TY JOUR TI FORM DIVERSITY OF <i>POPULUS NIGRA L., P. LAURIFOLIA LEDEB. </i>AND <i>P. × JRTYSCHENSIS </i>CHANG Y. YANG IN THE NORTH-WESTERN PART OF THE ALTAI-SAYANIAN MOUNTAIN AREA KW JO Bulletin of Kemerovo State University. Series: Biological, Engineering and Earth Sciences AU Klimov, A.V. AU Proshkin, B.V. PY 2017 IS 1 PB Kemerovo State University