APA (7th ed.) Citation

Voltaire. (1961). Philosophical letters. Prentice Hall.

Chicago Style (17th ed.) Citation

Voltaire. Philosophical Letters. Upper Saddle River, NJ: Prentice Hall, 1961.

MLA (9th ed.) Citation

Voltaire. Philosophical Letters. Prentice Hall, 1961.

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