@inbook{1107715292, author={James A. Russell}, editor={Hall, Jesse B. and Schmidt, Gregory A. and Kress, John P.}, title={Assessment of Severity of Illness}, booktitle={Principles of Critical Care, 4e}, publisher={McGraw-Hill Education}, address={New York, NY}, year={2015}, url={accessanesthesiology.mhmedical.com/content.aspx?aid=1107715292} }