APA (7th ed.) Citation

Schumann, R., Thompson, M., & Fowke, P. Adagio & Allegro in A flat op. 70.

Chicago Style (17th ed.) Citation

Schumann, Robert, Michael Thompson, and Philip Fowke. Adagio & Allegro in A Flat Op. 70.

MLA (9th ed.) Citation

Schumann, Robert, et al. Adagio & Allegro in A Flat Op. 70.