2BF9:
reference: Conformational flexibility in a small globular hormone: x-ray analysis of avian pancreatic polypeptide at 0.98-A resolution., Glover I, Haneef I, Pitts J, Wood S, Moss D, Tickle I, Blundell T, Biopolymers. 1983 Jan;22(1):293-304. PMID: 6673760

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