- Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales XV-58

1983. Bogotas, D.E. 109 pp. fp. (portrait van der Hammen), many figs./plts. Issue, dedicated to Thomas van der Hammen, with list of hids publications and a collection of papers mainly of a paleobotanical nature. Orig. wrps. covers with minor traces of use only, contents very good, lg4to.