Novak, J. D., & Cañas A. J. (2006). The Origins of the Concept Mapping Tool and the Continuing Evolution of the Tool (higher resolution for printing). Information Visualization Journal, 5, 175-184. Consultado (11/10/2011) en http://cmap.ihmc.us/Publications/ResearchPapers/OriginsOfConceptMappingTool.pdf