TY - RPRT TI - Crosstolerance between butorphanol and morphine in rats. AU - Y Z Feng AU - M Narita AU - Y T Tseng AU - B Hoskins AU - I K Ho PY - 1994 DO - 10.1016/0091-3057(94)90084-1 UR - https://pubmed.ncbi.nlm.nih.gov/7862721/ ID - 7862721 ER -