APA (7th ed.) Citation

Wright, M. H. (1957). The Butterfield Overland Mail one hundred years ago. [publisher not identified].

Chicago Style (17th ed.) Citation

Wright, Muriel H. The Butterfield Overland Mail One Hundred Years Ago. [Place of publication not identified]: [publisher not identified], 1957.

MLA (9th ed.) Citation

Wright, Muriel H. The Butterfield Overland Mail One Hundred Years Ago. [publisher not identified], 1957.