1ETP:
reference: Crystal structure of the dihaem cytochrome c4 from Pseudomonas stutzeri determined at 2.2A resolution., Kadziola A, Larsen S, Structure 1997 Feb 15;5(2):203-16. PMID: 9032080

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