FRIEDMAN, Alon, SMIRAGLIA, Richard P. Nodes and arcs: concept map, semiotics, and knowledge organization. In: Journal of documentation. 2013, 69(1), 27-48. doi:10.1108/00220411311295315. ISSN 0022-0418.
Dostupný komerčně z DK Emerald (DOI, Licence NK ČR): http://dx.doi.org/10.1108/00220411311295315.