Jeffreys, H. (1962). Earth: :Its origin history and physical constitution/4th ed (4th ed.). university press.
استشهاد بنمط شيكاغوJeffreys, Harold. Earth: :Its Origin History and Physical Constitution/4th Ed. 4th ed. Cambridge: university press, 1962.
MLA استشهادJeffreys, Harold. Earth: :Its Origin History and Physical Constitution/4th Ed. 4th ed. university press, 1962.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.