Benjamin W. Haynes
Unknown Author
G. N. Baturin
G. P. Glasby
Joseph Moses Botbol
Library of Congress. Congressional Research Service.
Benjamin V Andrews
International Symposium on Geology and Geochemistry of Manganese (2nd 1976 Sydney, N.S.W.)
Mark Salkind
Wang, Chenghou.
Frank T. Manheim
Ronald Keith Sorem
Yang Li
Danuta Trokowicz
David A. Larson
William Robert Reinhart
J. Z. Frazer