Gaya APA

Fletcher, W., Hoffman, S, (. (1987). Exploration Geochemistry : Design and Interpretation of Soil Surveys Volume 3 . New Mexico: society of economics geologist.

Gaya MLA

Fletcher, W.K., Hoffman, S.J, (a.o). "Exploration Geochemistry : Design and Interpretation of Soil Surveys Volume 3". New Mexico: society of economics geologist, 1987. Text.