1. Characteristics of Neotropical páramo vegetation and its subantarctic relations;Cleef,1978
2. Altitudinal sequence of the vegetation of Páramos of the Cordillera Oriental, Columbia;Cleef,1979
3. Cleef, A.M., in press. The Vegetation of the Páramos of the Colombian Cordillera Oriental Dissertationes Botinacae. J. Kramer, Vaduz.
4. Late Quaternary glacial and vegetational sequence in Valle de Lagunillas, Sierra Nevada del Cocuy, Columbia;Gonzales;Leidse Geol. Meded.,1965
5. Pollen rain in relation to arboreal vegetation in the Cordillera Oriental;Grabandt;Rev. Palaeobot. Palynol.,1980