Regional Anesthesia: The Journal of Neural Blockade in Obstetrics, Surgery, & Pain Control Jan 1990, 15 (1) 26-30; DOI: 10.1136/rapm-00115550-199015010-00007
Regional Anesthesia: The Journal of Neural Blockade in Obstetrics, Surgery, & Pain Control Jul 1995, 20 (4) 296-302; DOI: 10.1136/rapm-00115550-199520040-00004