| 1Y8I: reference: A new relaxed state in horse methemoglobin characterized by crystallographic studies., Sankaranarayanan R, Biswal BK, Vijayan M, Proteins 2005 Aug 15;60(3):547-51. PMID: 15887226 |
This OCA 
Structure page
uses Jmol,
developed by the Jmol Development Team
(documentation).