Παραπομπή APA

Baker, R. H. F. (1971). Astronomy (9.).

Παραπομπή Chicago Style

Baker, Robert H; Fredrick. Astronomy. 9. Van Nostrand Reinhold Co., New York, 1971.

Παραπομπή MLA

Baker, Robert H; Fredrick. Astronomy. 9. 1971.