APA-viite

Calvo-Obando, A., & Ortiz-Malavasi, E. (2012). The fragmentation degree of forest cover in the Fitogeografic Units (FU) of Costa Rica was studied during three years: 1997, 2000 and 2005.

Chicago-tyylinen lähdeviittaus

Calvo-Obando, Ana, ja Edgar Ortiz-Malavasi. The Fragmentation Degree of Forest Cover in the Fitogeografic Units (FU) of Costa Rica Was Studied During Three Years: 1997, 2000 and 2005. 2012.

MLA-viite

Calvo-Obando, Ana, ja Edgar Ortiz-Malavasi. The Fragmentation Degree of Forest Cover in the Fitogeografic Units (FU) of Costa Rica Was Studied During Three Years: 1997, 2000 and 2005. 2012.

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