RT Journal Article SR Electronic T1 Erector spinae block: transverse superior to paramedian sagittal? JF Regional Anesthesia & Pain Medicine JO Reg Anesth Pain Med FD BMJ Publishing Group Ltd SP 422 OP 422 DO 10.1136/rapm-2018-100141 VO 44 IS 3 A1 Alexander Philip A1 Vipul Kaushik YR 2019 UL http://rapm.bmj.com/content/44/3/422.1.abstract AB