APA

Etter A., Villa, .Andean forests and farming systems in part of the eastern Cordillera (colombia). : .

Chicago

Etter Andrés, Villa, .Andean forests and farming systems in part of the eastern Cordillera (colombia). : .

Harvard

Etter A., Villa, .Andean forests and farming systems in part of the eastern Cordillera (colombia). : .

MLA

Etter Andrés, Villa, .: . .