Martin, MD, Gavin, Maximilian Hartmannsgruber, MD, Edward Riley, MD, and Garen Manvelian, MD. 2006. “Single-Dose Extended-Release Epidural Morphine for Pain After Hip Arthroplasty”. Journal of Opioid Management 2 (4):209-18. https://doi.org/10.5055/jom.2006.0033.