Urey, Harold Clayton The planets, their origin and development. - New Haven Yale University Press 1952. - xvii, 245 p. illus. (1 fold.) 25 cm. - Yale University. Mrs. Hepsa Ely Silliman memorial lectures 1951 . - Mrs. Hepsa Ely Silliman memorial lectures. 30. . Bibliographical footnotes. LCCN: 52005359 Subjects--Topical Terms: Planetary theory. LC Class. No.: QB361 / .U7 Dewey Class. No.: 521.5