Ε. Posnjak

H. E. Merwin

Carnegie Institution for Science

George Tunell

University of California, Santa Barbara

N. L. Bowen

California State University, East Bay

J. W. Greig

Carnegie Institution for Science

N. L. Bowen

Carnegie Institution for Science

J. F. Schairer

Carnegie Institution for Science

E. T. Allen

Bethlehem Area School District

E. P. Henderson

Smithsonian Institution

C. J. Ksanda

Geophysical Laboratory

Clarence S. Ross

United States Geological Survey

Carnegie Institution for Science

Geophysical Laboratory

United States Geological Survey

University of Chicago

University of California, Los Angeles

Yale University

Institute of Mineralogy

California State University, East Bay

American University of Paris

Princeton University