APA (7th ed.) Citation

Beethoven, L. v., Schreier, P., & Olbertz, W. Adelaide: Op. 46.

Chicago Style (17th ed.) Citation

Beethoven, Ludwig van, Peter Schreier, and Walter Olbertz. Adelaide: Op. 46.

MLA (9th ed.) Citation

Beethoven, Ludwig van, et al. Adelaide: Op. 46.