Editors by W. H. Twenhopel. (1953). Principles of invertebrate paleontology: A revised and enlarged (2nd ed.). McGraw - hill.
Chicago Style (17. basım) AtıfEditors by W. H. Twenhopel. Principles of Invertebrate Paleontology: A Revised and Enlarged. 2nd ed. New York: McGraw - hill, 1953.
MLA (9th ed.) AtıfEditors by W. H. Twenhopel. Principles of Invertebrate Paleontology: A Revised and Enlarged. 2nd ed. McGraw - hill, 1953.
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