APA (7th ed.) Citation

Watt, D. S. (1957). Mathematics is easy / by D. Watt. Princes.

Chicago Style (17th ed.) Citation

Watt, D. S. Mathematics Is Easy / by D. Watt. Princes, 1957.

MLA (9th ed.) Citation

Watt, D. S. Mathematics Is Easy / by D. Watt. Princes, 1957.

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