Imlay, Ralph Willard 1908-1989 Characteristic lower Cretaceous megafossils from northern Alaska / by Ralph W. Imlay. -- Washington : United States Government Printing Office, 1961 - 74 p., [20] h. de lam. -- (Geological Survey Professional Paper ; 335). Subjects--Topical Terms: AlaskaCretácicoPaleontología Universal Decimal Class. No.: 551.763(798)