Piper D.Z. Geochemistry of minor elements in the Monterey Formation,California:seawater chemistry of deposition / D.Z.Piper,C.M.Isaacs, 1995. - IV,41 p. p. - Текст : непосредственный.
Piper D.Z. Cooccurrence of Fe-,Fe-Ca, and Ca-phosphate minerals in concretions within the Monterey Formation : A record of uplift of the Santa Maria Basin,California / D.Z.Piper,C.M.Isaacs,M.D.Medrano, 1993. - III,C 15 p. 15 p. - Текст : непосредственный.