APA (7th ed.) Citation

Thoreau, H. D., Smith, E. O. P., & Hill, E. B. (1942). Henry D. Thoreau to Elizabeth Oakes Smith.

Chicago Style (17th ed.) Citation

Thoreau, Henry David, Elizabeth Oakes Prince Smith, and Edwin Bliss Hill. Henry D. Thoreau to Elizabeth Oakes Smith. 1942.

MLA (9th ed.) Citation

Thoreau, Henry David, et al. Henry D. Thoreau to Elizabeth Oakes Smith. 1942.