APA (7th ed.) Citation

Barthel, H., Boeck, H., & Elsner, J. Methodik des Chemieunterrichts.

Chicago Style (17th ed.) Citation

Barthel, Helmut, Helmut Boeck, and Johannes Elsner. Methodik Des Chemieunterrichts. Potsdam.

MLA (9th ed.) Citation

Barthel, Helmut, et al. Methodik Des Chemieunterrichts.

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