Williams, G. E. Megacycles long-term episodicity in earth and planetary history G. E. Williams - Stroudsburg Hutchinson Ross Publishing Co. 1981 - xvii+434p. illus; maps - Benchmark Papers in Geology; No. 57 . ISBN: 879333669 Subjects--Topical Terms: MegacyclesEpisodicityPlanetary Systems Universal Decimal Class. No.: 551.1/.4 / WIL