Volkert R.A. Geology,geochemistry, and technostratigraphic reletions of the crystalline basement beneath the coastal plain of New Jersy and contiguous areas / R.A.Volkert,A.A.Jr.Drake,P.J.Sugarman, 1996. - 48 p. - Текст : непосредственный.
Volkert R.A. Late-Proterozoic diabase dikes of the New Jersey Highlands-a remnant of lapetan rifting in the north-central Appalachians / R.A.Volkert,J.H.Puffer, 1995. - 21 p. - Текст : непосредственный.