RT Journal Article SR Electronic T1 Intrathecal Morphine and Fentanyl for Labor Analgesia: Efficacy and Adverse Effects JF Regional Anesthesia: The Journal of Neural Blockade in Obstetrics, Surgery, & Pain Control JO Reg Anesth Pain Med FD BMJ Publishing Group Ltd SP 51 OP 51 DO 10.1136/rapm-00115550-199318021-00051 VO 18 IS Suppl 2 A1 Lawrence E. Caldwell A1 Mark A. Rosen A1 Sol M. Shnider YR 1993 UL http://rapm.bmj.com/content/18/Suppl_2/51.abstract AB