1N3Z:
reference: The unswapped chain of bovine seminal ribonuclease: Crystal structure of the free and liganded monomeric derivative., Sica F, Di Fiore A, Zagari A, Mazzarella L, Proteins 2003 Aug 1;52(2):263-71. PMID: 12833549

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