APA   Click to copy
Colwell, R. K. (1973). Competition and coexistence in a simple tropical community. The American Naturalist, 107, 737–760.

Chicago/Turabian   Click to copy
Colwell, Robert K. “Competition and Coexistence in a Simple Tropical Community.” The American Naturalist 107 (1973): 737–760.

MLA   Click to copy
Colwell, Robert K. “Competition and Coexistence in a Simple Tropical Community.” The American Naturalist, vol. 107, University of Chicago Press, 1973, pp. 737–60.

@article{colwell1973a,
  title = {Competition and coexistence in a simple tropical community},
  year = {1973},
  journal = {The American Naturalist},
  pages = {737-760},
  publisher = {University of Chicago Press},
  volume = {107},
  author = {Colwell, Robert K}
}