The BSAE, S.G. 2015. Preemptive Analgesic Efficacy of Tramadol, Butorphanol, and Flurbiprofen in Lumpectomy: A Randomized, Controlled and Double-blind Trial. Science Insights. 11, 2 (Feb. 2015), 322–329. DOI:https://doi.org/10.15354/si.14.ar006.