APA (7th ed.) Citation

Haanel, C. F., & Rudolph, H. (2016). Das Master Key System (2. Taschenbuchauflage.). Inspired Mind.

Chicago Style (17th ed.) Citation

Haanel, Charles F., and Helmar Rudolph. Das Master Key System. 2. Taschenbuchauflage. [Waldkirchen]: Inspired Mind, 2016.

MLA (9th ed.) Citation

Haanel, Charles F., and Helmar Rudolph. Das Master Key System. 2. Taschenbuchauflage. Inspired Mind, 2016.