00730nam a22002051  45000010005000000030008000050050017000130080039000300350018000690400031000870410008001180820025001261000021001512450092001722600113002643000037003775040037004146500036004517000037004876302BD-RjUL20211208234224.0140109s1965    ne a     b    001 0 eng  a(BD-RjUL)6342  aDLC/ICUcICUdBD-RjULbeng  aeng04220a530.12bFRJ 19651 aFröman, Nanny.10aJWKB approximation :bcontributions to the theory /cNanny Fröman, Per Olof Fröman.  aAmsterdam,bNorth-Holland Pub. Co.; [sole distributors for U.S.A.: Interscience Publishers, New York]c1965.  aviii, 138 p. :billus. ;c23 cm.  aIncludes bibliography and index. 0aPerturbation (Quantum dynamics)1 aFröman, Per Olofejoint author