APA (7th ed.) Citation

Schumann, R., Boetticher, W., & Theopold, H. (1989). Humoreske opus 20 (Urtext.). Henle.

Chicago Style (17th ed.) Citation

Schumann, Robert, Wolfgang Boetticher, and Hans-Martin Theopold. Humoreske Opus 20. Urtext. München: Henle, 1989.

MLA (9th ed.) Citation

Schumann, Robert, et al. Humoreske Opus 20. Urtext. Henle, 1989.