00489    a2200157   4500020001500000020001800015082001100033090001300044100002000057245006400077260003400141300001100175942002400186999001700210952010400227  a0125316801  a978012531680404a515.35  c323d3231 aOvsiannikov, L.10aGroup analysis of differential equations /cL. Ovsiannikov.  a[S.l.] :bAcademic Pr,c1978.  a432 p.  aSNScBKk515.35 OVS  c28958d28958  00104070aSNSbSNSd2016-05-26l1o515.35 OVSpSNS0000236r2024-07-03s2023-04-12w2016-05-26yBK