00370nam a2200121 a 450000500170000008200160001710000200003324500320005326000360008530000270012149000550014863000450020320251203091010.0  a513.35bWAS  aWasow, Wolfgang  aLinear turning point theory  aNew YorkbSpringer-Verlagc1985  aix, 246 p.b22 cm.cHB  aApplied mathematical sciencesdv.54, 0-387-96046-5  aDifferential equations-asymptotic theory