APA (7th ed.) Citation

Frost, R., & Faggen, R. (1998). Early poems. Penguin Books.

Chicago Style (17th ed.) Citation

Frost, Robert, and Robert Faggen. Early Poems. New York [etc.]: Penguin Books, 1998.

MLA (9th ed.) Citation

Frost, Robert, and Robert Faggen. Early Poems. Penguin Books, 1998.

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