Robbins S.L. Gravity and aeromagnetic studies of the Powder River Basin and surrounding areas,southeastern Montana,northeastern Wyoming, and western South Dakota / S.L.Robbins, 1994. - IV,R17 p. p. - Текст : непосредственный.
Robbins S.L. Complete Bouguer and isostatic residual gravity maps of the Anadarko Basin,Wichita Mountains,and surrounding areas,Oklahoma,Kansas,Texas,and Colorado / S.L.Robbins,G.R.(jr.)Keller, 1992. - III,11 p p. - Текст : непосредственный.