Williams, G. (1966). A study of a seminal defect in Hereford bulls and also of the effect on fertility of the movement of cattle to a new environment. University of London.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)Williams, Gareth. A Study of a Seminal Defect in Hereford Bulls and Also of the Effect on Fertility of the Movement of Cattle to a New Environment. University of London, 1966.
Trích dẫn kiểu MLA (xuất bản lần thứ 8)Williams, Gareth. A Study of a Seminal Defect in Hereford Bulls and Also of the Effect on Fertility of the Movement of Cattle to a New Environment. University of London, 1966.
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