APA (7th ed.) Citation

Keim, D. B. R. (2000). Sheridan's troopers on the borders. Digital Scanning.

Chicago Style (17th ed.) Citation

Keim, De B. Randolph. Sheridan's Troopers on the Borders. Scituate, Mass: Digital Scanning, 2000.

MLA (9th ed.) Citation

Keim, De B. Randolph. Sheridan's Troopers on the Borders. Digital Scanning, 2000.