Power, Mary E.; Tilman, David; Estes, James A.; Menge, Bruce A.; Bond, William J.; Mills, L. Scott; Daily, Gretchen; Castilla, Juan Carlos; Lubchenco, Jane; Paine, Robert T. (1 September 1996). "Challenges in the Quest for Keystones". BioScience. 46 (8): 609–620. doi:10.2307/1312990. ISSN0006-3568.
Power, Mary E.; Tilman, David; Estes, James A.; Menge, Bruce A.; Bond, William J.; Mills, L. Scott; Daily, Gretchen; Castilla, Juan Carlos; Lubchenco, Jane; Paine, Robert T. (1 September 1996). "Challenges in the Quest for Keystones". BioScience. 46 (8): 609–620. doi:10.2307/1312990. ISSN0006-3568.
Power, Mary E.; Tilman, David; Estes, James A.; Menge, Bruce A.; Bond, William J.; Mills, L. Scott; Daily, Gretchen; Castilla, Juan Carlos; Lubchenco, Jane; Paine, Robert T. (1 September 1996). "Challenges in the Quest for Keystones". BioScience. 46 (8): 609–620. doi:10.2307/1312990. ISSN0006-3568.