APA (7th ed.) Citation

Funk, W., & Lewis, N. (1972). Thirty days to a more powerful vocabulary (Primera edición.). Wilfred Funk.

Chicago Style (17th ed.) Citation

Funk, Wilfred, and Norman Lewis. Thirty Days to a More Powerful Vocabulary. Primera edición. New York: Wilfred Funk, 1972.

MLA (8th ed.) Citation

Funk, Wilfred, and Norman Lewis. Thirty Days to a More Powerful Vocabulary. Primera edición. Wilfred Funk, 1972.

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