Babu, P. Ramesh. Signals and systems / - 5th ed. - Chennai : Scitech Publications (India) Pvt. ltd., c2018. - 11.14/ B.5 p. : ill. ; 24 cm. Includes bibliographical references and index. ISBN: 9789385983405 LC Class. No.: 22 Dewey Class. No.: 621.3822320 / BAB