Sarsour, K., Morin, C. M., Foley, K., Kalsekar, A., & Walsh, J. K. (2010). Association of insomnia severity and comorbid medical and psychiatric disorders in a health plan-based sample: Insomnia severity and comorbidities. Sleep Medicine, 11(1), 69-74. https://doi.org/10.1016/j.sleep.2009.02.008

Sarsour, Khaled, Charles M. Morin, Kathleen Foley, Anupama Kalsekar, and James K. Walsh. "Association of Insomnia Severity and Comorbid Medical and Psychiatric Disorders in a Health Plan-based Sample: Insomnia Severity and Comorbidities." Sleep Medicine 11, no. 1 (2010): 69-74. https://doi.org/10.1016/j.sleep.2009.02.008.

Sarsour, Khaled, et al. "Association of Insomnia Severity and Comorbid Medical and Psychiatric Disorders in a Health Plan-based Sample: Insomnia Severity and Comorbidities." Sleep Medicine, vol. 11, no. 1, 2010, pp. 69-74, https://doi.org/10.1016/j.sleep.2009.02.008.