APA (7th ed.) Citation

made simple books & Whitehead, G. (1989). Commerce: Made simple. made simple books.

Chicago Style (17th ed.) Citation

made simple books and G. Whitehead. Commerce: Made Simple. Oxford: made simple books, 1989.

MLA (8th ed.) Citation

made simple books and G. Whitehead. Commerce: Made Simple. made simple books, 1989.

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