APA استشهاد

Longwell, C. R. (1957). Outlines of physical geology (2nd ed.). John willey & sons.

استشهاد بنمط شيكاغو

Longwell, Chester R. Outlines of Physical Geology. 2nd ed. New york: John willey & sons, 1957.

MLA استشهاد

Longwell, Chester R. Outlines of Physical Geology. 2nd ed. John willey & sons, 1957.