APA (7th ed.) Citation

Heyden, T. (2012). "Mit Doppel-F": Ludwig und Franz Ruff.

Chicago Style (17th ed.) Citation

Heyden, Thomas. "Mit Doppel-F": Ludwig Und Franz Ruff. 2012.

MLA (9th ed.) Citation

Heyden, Thomas. "Mit Doppel-F": Ludwig Und Franz Ruff. 2012.

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