00318nam a2200109Ia 4500008004100000020001400041082001600055100001900071245006100090260004900151300000800200191014s9999    xx            000 0 und d  a444104380  a515.35bKCK  aWiktor Eckhaus 0aMatched Asymptoic Expansions and Singular Perturbations   aNew York bElsevier Publishing Companyc1973  a145