APA استشهاد

Ahrens, L. H. (1965). Distribution of the elements in our planet. McGraw-Hill.

استشهاد بنمط شيكاغو

Ahrens, L. H. Distribution of the Elements in Our Planet. New York: McGraw-Hill, 1965.

MLA استشهاد

Ahrens, L. H. Distribution of the Elements in Our Planet. McGraw-Hill, 1965.