@inbook{1199674025, author={Erin J. Ciampa and Philip E. Hess}, editor={Hess, Philip E. and Li, Yunping and Kowalczyk, John J. and Stiles, Justin K.}, title={Refractory Pain During Labor Epidural Analgesia}, booktitle={Obstetric Anesthesia: Quick References & Practical Guides}, publisher={McGraw Hill}, address={New York, NY}, year={2023}, url={obgyn.mhmedical.com/content.aspx?aid=1199674025} }