00351nam a2200121Ia 4500008004100000020001800041040003800059100002200097245004400119250000800163260004100171300001700212211217s9999    xx            000 0 und d  a0-04-510049-7  cJayakar Knowledge Resource Centre  aGiacagllia, G E O 0aPurbation methods in non-linear systems  a1st  bGeorge Allen and UnwinaLondonc1972  aviii,369p p.