1. Jørgensen PM, Ulloa Ulloa C: Seed plants of the High Andes of Ecuador – a checklist. AAU Reports 1994, 34: 1-443.
2. Jørgensen PM, León-Yanez S, Eds: Catalogue of the vascular plants of Ecuador. Monographs in Systematic Botany from the Missouri Botanical Garden 1999., 75:
3. Ulloa Ulloa C, Jørgensen PM: Arboles y arbustos de los Andes del Ecuador. AAU Reports 1993, 30: 1-263.
4. Sparre G, Harling B: Flora of Ecuador (various authors). Council for Nordic Publications in Botany, 1978–2006;
5. Espinosa B: Estudios botanicos en el sur del Ecuador. I. Loja-Catamayo-Malacatos- Vilcabamba. – Loja, Universidad Nacional. 1948.