Collado, MD, PhD, Francisco, and Luis M. Torres, MD, PhD. 2018. “Association of Transdermal Fentanyl and Oral Transmucosal Fentanyl Citrate in the Treatment of Opioid naïve Patients With Severe Chronic Noncancer Pain”. Journal of Opioid Management 4 (2):111-15. https://doi.org/10.5055/jom.2008.0016.