American Berkshire association. (1883). The swine breeder's manual. The American Berkshire association.
Chicago-viite (17. p.)American Berkshire association. The Swine Breeder's Manual. Springfield, Ill.: The American Berkshire association, 1883.
MLA-viite (9. p.)American Berkshire association. The Swine Breeder's Manual. The American Berkshire association, 1883.
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