Cita APA (7th ed.)
Hale, G. E. (1897). The Yerkes Observatory of the University of Chicago.
Cita Chicago (17th ed.)
Hale, George Ellery. The Yerkes Observatory of the University of Chicago. o.O, 1897.
Cita MLA (9th ed.)
Hale, George Ellery. The Yerkes Observatory of the University of Chicago. 1897.
Atenció: Aquestes cites poden no estar 100% correctes.