Natural environment of early food production north of Mesopotamia. - Washington, D.C. enthält: Radiocarbon dates of Makato Drift in Minnesota / H. E. Wright, Jr. ; Meyer Rubin. - Washington, D.C - Wright, H. E. (Herbert Edgar) 1917- (Science ; 161.1968, no. 3839, S. 334-339 : 3 Ill. ; 1 Tab., 1968)