J. Hastings, W. Ceusters, B. Smith, und K. Mulligan. Proceedings of the 2nd International Conference on Biomedical Ontology, Volume 833 von CEUR Workshop Proceedings, (30.07.2011)
K. Henderson. U.S. Department of Education, Office of Special Education and Rehabilitative Services; U.S. Department of Education, Office of Special Education Programs, Washington, DC, (August 2008)