APA (7th ed.) Citation

Twain, M., & Gardner, G. (2011). A tramp abroad. Blackstone Audio, Inc..

Chicago Style (17th ed.) Citation

Twain, Mark, and Grover Gardner. A Tramp Abroad. Ashland, OR: Blackstone Audio, Inc., 2011.

MLA (8th ed.) Citation

Twain, Mark, and Grover Gardner. A Tramp Abroad. Blackstone Audio, Inc., 2011.

Warning: These citations may not always be 100% accurate.