APA (7th ed.) Citation

De Voto, B., & Twain, M. (1942). Mark Twain at work. Harvard University Press.

Chicago Style (17th ed.) Citation

De Voto, Bernard, and Mark Twain. Mark Twain at Work. Cambridge, Mass.: Harvard University Press, 1942.

MLA (9th ed.) Citation

De Voto, Bernard, and Mark Twain. Mark Twain at Work. Harvard University Press, 1942.