Semper, K. (1881). The Natural conditions of existence as they affect animal life. With 2 maps and 106 woodcuts (1a. ed.). C. Kegan Paul & Co., 1 Paternoster Square.
Cita Chicago (17th ed.)Semper, Karl. The Natural Conditions of Existence as They Affect Animal Life. With 2 Maps and 106 Woodcuts. 1a. ed. Londres: C. Kegan Paul & Co., 1 Paternoster Square, 1881.
Cita MLA (9th ed.)Semper, Karl. The Natural Conditions of Existence as They Affect Animal Life. With 2 Maps and 106 Woodcuts. 1a. ed. C. Kegan Paul & Co., 1 Paternoster Square, 1881.
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