APA (7th ed.) Citation

Voltaire. (1961). Philosophical letters / by Voltaire. Bobbs-Merrill.

Chicago Style (17th ed.) Citation

Voltaire. Philosophical Letters / by Voltaire. Bobbs-Merrill, 1961.

MLA (9th ed.) Citation

Voltaire. Philosophical Letters / by Voltaire. Bobbs-Merrill, 1961.

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