Dyfyniad APA

Calvo, J., Quesada, C., Sánchez, A., González, P., Watson, V., & Bolaños, R. (1999). Forest cover in protected areas of Costa Rica between 1986/7 and 1996/7.

Dyfyniad Arddull Chicago

Calvo, Julio, Carlos Quesada, Arturo Sánchez, Pablo González, Vicente Watson, y Rafael Bolaños. Forest Cover in Protected Areas of Costa Rica between 1986/7 and 1996/7. 1999.

Dyfyniad MLA

Calvo, Julio, et al. Forest Cover in Protected Areas of Costa Rica between 1986/7 and 1996/7. 1999.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.