00497nam a2200157Ia 4500003000900000008004100009040001600050080001500066100001600081245011600097260003300213300001400246650002700260650002700287700002500314IN-BaIIA211028s9999    xx            000 0 eng d  cIIA Library  a517.9bELS  aElsgolts, L 0aDifferential equations and calculus of variationscL. Elsgolts                                                   aMoscowbMIR Publishersc1973  axii,146p.  aCalculus of variations  aDifferential equations  aYankovsky,George tr.