Source

(1) "Drug Retention Times," Center for Human Reliability Studies (Oak Ridge, TN: Oak Ridge Institute for Science and Education, May 2007), pp. 2-4.
http://www.osti.gov/scitech/b…
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(2) "Clinical Drug Testing in Primary Care," Technical Assistance Publication (TAP) 32, Substance Abuse and Mental Health Services Administration, Clinical Drug Testing in Primary Care (Rockville, MD: U.S. Departent of Health and Human Services, 2012), p. 5
http://www.kap.samhsa.gov/pro…
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(3) Christo,Paul J.; Manchikanti, Laxmaiah; Ruan, Xiulu; Bottros, Michael; Hansen, Hans; Solanki, Daneshvari R.; Jordan, Arthur E.; and Colson, James , "Urine Drug Testing In Chronic Pain," Pain Physician (Paducah, KY: American Society of Interventional Pain Physicians, March/April 2011), Vol. 14, Issue 2, p. 130.
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