APA (7th ed.) Citation

Hafen. (1981). How to live longer. Prentice-Hall.

Chicago Style (17th ed.) Citation

Hafen. How to Live Longer. New Jersey: Prentice-Hall, 1981.

MLA (8th ed.) Citation

Hafen. How to Live Longer. Prentice-Hall, 1981.

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