1. a Purdue Pharma. L.P.444 Saw Mill River Road, Ardsley, NY 10502, USA
2. b Purdue Pharma. L.P.444 Saw Mill River Road, Ardsley, NY 10502, USA
3. c Oakwood Laboratories, 7670 First Place, Oakwood, OH 44146, USA
4. d University of Kentucky, College of Pharmacy, Rose Street, Rm 327G, Lexington, KY 40535-0082, USA