Ellen S.D. Hillside materials and slopes of the San Francisco bay region,California / S.D.Ellen,C.M.Wentworth, 1995. - 215 p. - Текст : непосредственный.
Geologic processes at the land surface / H.G.Wilshire,K.A.Howard,C.M.Wentworth,H.Gibbons, 1996. - 41 p. - Текст : непосредственный.