@inbook{1000094112, author={Carol A. Warfield and Zahid H. Bajwa}, title={B. Injections and Neurolytic Therapies for Pain}, booktitle={Principles & Practice of Pain Medicine, 2e}, publisher={The McGraw-Hill Companies}, address={New York, NY}, year={2004}, url={accessanesthesiology.mhmedical.com/content.aspx?aid=1000094112} }