Dyfyniad APA

HOLMES, A. Principles of physical geology chapter XX-XXI(619-1288).-- 2nd ed. ELBS and Nelson.

Dyfyniad Arddull Chicago

HOLMES, Arthur. Principles of Physical Geology Chapter XX-XXI(619-1288).-- 2nd Ed. London: ELBS and Nelson.

Dyfyniad MLA

HOLMES, Arthur. Principles of Physical Geology Chapter XX-XXI(619-1288).-- 2nd Ed. ELBS and Nelson.

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