Cita APA (7th ed.)

Rydberg, P. A. (1906). Flora of Colorado. Experiment Station.

Cita Chicago (17th ed.)

Rydberg, Per Axel. Flora of Colorado. Fort Collins, Colo.: Experiment Station, 1906.

Cita MLA (8th ed.)

Rydberg, Per Axel. Flora of Colorado. Experiment Station, 1906.