Okamoto, BP, Yoshiaki, Satoru Tsuneto, MD, PhD, Mamiko Tsugane, PhD, Tatsuya Takagi, PhD, and Etsuko Uejima, PhD. 2018. “A Retrospective Chart Review of Opioid-Induced Nausea and Somnolence on Commencement for Cancer Pain Treatment”. Journal of Opioid Management 6 (6):431-34. https://doi.org/10.5055/jom.2010.0041.