APA Citation

Vacca, J. R. (2005). The World`s 20 Greatest Unsolved Problems. New Jersey: Prientice Hall.

Chicago Style Citation

Vacca, John R. The World`s 20 Greatest Unsolved Problems. New Jersey: Prientice Hall, 2005.

MLA Citation

Vacca, John R. The World`s 20 Greatest Unsolved Problems. New Jersey: Prientice Hall, 2005.

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