8GCH:
reference: Gamma-chymotrypsin is a complex of alpha-chymotrypsin with its own autolysis products., Harel M, Su CT, Frolow F, Silman I, Sussman JL, Biochemistry 1991 May 28;30(21):5217-25. PMID: 2036388

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