Williams, J. W. (1912). Obstetrics, a text-book for the use of students and practitioners (3d enl. and rev. ed., with sixteen plates and six hundred and sixty-eight illustrations in the text.). D. Appleton and Company.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)Williams, J. Whitridge. Obstetrics, a Text-book for the Use of Students and Practitioners. 3d enl. and rev. ed., with sixteen plates and six hundred and sixty-eight illustrations in the text. New York and London: D. Appleton and Company, 1912.
Trích dẫn kiểu MLA (xuất bản lần thứ 8)Williams, J. Whitridge. Obstetrics, a Text-book for the Use of Students and Practitioners. 3d enl. and rev. ed., with sixteen plates and six hundred and sixty-eight illustrations in the text. D. Appleton and Company, 1912.
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