National Research Council & Curtis, R. B. (1969). The Invisible university: Postdoctoral education in the United States. Report of a study conducted under the auspices of the National Research Council. National Academy of Sciences.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)National Research Council và Richard Bertram Curtis. The Invisible University: Postdoctoral Education in the United States. Report of a Study Conducted Under the Auspices of the National Research Council. Washington: National Academy of Sciences, 1969.
Trích dẫn kiểu MLA (xuất bản lần thứ 9)National Research Council và Richard Bertram Curtis. The Invisible University: Postdoctoral Education in the United States. Report of a Study Conducted Under the Auspices of the National Research Council. National Academy of Sciences, 1969.