Sneddon, Ian Naismith. Elements of partial differential equations / Ian Naismith Sneddon. - New York, McGraw-Hill, 1957. - 327 p. illus. 24 cm. - International series in pure and applied mathematics . LCCN: 56006972 Subjects--Topical Terms: Differential equations, Partial. LC Class. No.: QA374 / .S6 Dewey Class. No.: 517.38