Packard, A. (1880). Guide to insects: And a treatise on those injurious and beneficial to crops for the use of colleges, farm schools and agriculturist (7th edition.). Henry Holt and Company.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)Packard, A.S. Guide to Insects: And a Treatise on Those Injurious and Beneficial to Crops for the Use of Colleges, Farm Schools and Agriculturist. 7th edition. New Delhi: Henry Holt and Company, 1880.
Trích dẫn kiểu MLA (xuất bản lần thứ 9)Packard, A.S. Guide to Insects: And a Treatise on Those Injurious and Beneficial to Crops for the Use of Colleges, Farm Schools and Agriculturist. 7th edition. Henry Holt and Company, 1880.
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