Larson, PhD, M. E. M., R. L. Berg, MS, and J. Flanagan, PhD. “Quantification of Oxycodone and Morphine Analytes in Urine: Assessment of Adherence”. Journal of Opioid Management, vol. 11, no. 6, Nov. 2015, pp. 489-00, doi:10.5055/jom.2015.0302.