APA (7th ed.) Citation

Parkinson, B., Hemmen, J., & Groh, K. (1987). Tropical landshells of the world. Verlag C. Hemmen.

Chicago Style (17th ed.) Citation

Parkinson, B., Jens Hemmen, and Klaus Groh. Tropical Landshells of the World. Wiesbaden, Western Germany: Verlag C. Hemmen, 1987.

MLA (9th ed.) Citation

Parkinson, B., et al. Tropical Landshells of the World. Verlag C. Hemmen, 1987.