2Q4G:
reference: Inhibition of human pancreatic ribonuclease by the human ribonuclease inhibitor protein., Johnson RJ, McCoy JG, Bingman CA, Phillips GN Jr, Raines RT, J Mol Biol. 2007 Apr 27;368(2):434-49. Epub 2007 Feb 9. PMID: 17350650

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).