Ahsan, Zafar Differential equations and their applications / by Zafar Ahsan - 2nd ed. - New Delhi : PHI Learning Private Limited , 2004 . - 514 p. Paper Back ISBN: 9788120325234 Subjects--Topical Terms: Differential EuqationsLinear equationsLaplace transform Dewey Class. No.: 515.35 / ZAF-D