1XCH:
reference: A myoglobin variant with a polar substitution in a conserved hydrophobic cluster in the heme binding pocket., Maurus R, Overall CM, Bogumil R, Luo Y, Mauk AG, Smith M, Brayer GD, Biochim Biophys Acta 1997 Aug 15;1341(1):1-13. PMID: 9300804

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