Berry, William B. N., Growth of a prehistoric time scale, based on organic evolution [print] William B. N. Berry. - San Francisco, W. H. Freeman (c)1968. - viii, 158 pages illustrations, maps ; 21 cm. LCCN: 68014224 //r69 Nat. Bib. No.: GB68-21213 Subjects--Topical Terms: Geological time. LC Class. No.: QE508.B534.G769 1968