Walter, H. E. (1949). Biology of the vertebrates: A comparative study of man and his animal allies (3rd ed.). The Macmillan.
Chicago-viite (17. p.)Walter, Herbert Eugene. Biology of the Vertebrates: A Comparative Study of Man and His Animal Allies. 3rd ed. New York: The Macmillan, 1949.
MLA-viite (9. p.)Walter, Herbert Eugene. Biology of the Vertebrates: A Comparative Study of Man and His Animal Allies. 3rd ed. The Macmillan, 1949.
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