Clapham, R. The Book of the Otter: A manual for sportsmen and naturalists.
Chicago Style (17th ed.) ZitazioaClapham, Richard. The Book of the Otter: A Manual for Sportsmen and Naturalists.
MLA (9th ed.) ZitazioaClapham, Richard. The Book of the Otter: A Manual for Sportsmen and Naturalists.
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