"Emotional Wellness Toolkit." Health Information, National Institutes of Health, www.nih.gov/health-information/emotional-wellness-toolkit. Accessed 9 July 2018.
"How Cells Communicate During Fight or Flight." Learn Genetics, Genetic Science Learning Center, learn.genetics.utah.edu/content/cells/fight_flight. Accessed 6 July 2018.
"Stress." Monitor on Psychology, American Psychological Association, www.apa.org/topics/stress/index.aspx. Accessed 6 July 2018.