APA (7th ed.) Citation

James, W., & James, H. (1920). The letters of William James. Longmans, Green.

Chicago Style (17th ed.) Citation

James, William, and Henry James. The Letters of William James. London: Longmans, Green, 1920.

MLA (9th ed.) Citation

James, William, and Henry James. The Letters of William James. Longmans, Green, 1920.