1. Autism and Developmental Disabilities Monitoring (ADDM) Network Surveillance Year, and 2010 Principal Investigators (2014). Prevalence of autism spectrum disorder among children aged 8 years-autism and developmental disabilities monitoring network, 11 sites, United States, 2010. Morbidity and mortality weekly report. Surveillance summaries (Washington, DC: 2002), 63(2), 1.
2. Centers for Disease Control and Prevention. (2014). CDC estimates 1 in 68 children has been identified with autism spectrum disorder. Retrieved from http://www.cdc.gov/media/releases/2014/p0327-autism-spectrumdisorder.html . Accessed 15 June 2016.
3. Dixon, M. R. (2014a). The PEAK relational training system: direct training module. Carbondale, IL: Shawnee Scientific Press.
4. Dixon, M. R. (2014b). The PEAK relational training system: generalization module. Carbondale, IL: Shawnee Scientific Press.
5. Dixon, M. R. (2015). The PEAK relational training system: equivalence module. Carbondale, IL: Shawnee Scientific Press.