APA (7th ed.) Citation

Helwing, B., & Helwing, B. (2011). Wilhelm Eilers.

Chicago Style (17th ed.) Citation

Helwing, Barbara, and B. Helwing. Wilhelm Eilers. 2011.

MLA (8th ed.) Citation

Helwing, Barbara, and B. Helwing. Wilhelm Eilers. 2011.

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