| 3KMF: reference: Direct determination of protonation states of histidine residues in a 2 A neutron structure of deoxy-human normal adult hemoglobin and implications for the bohr effect., Kovalevsky AY, Chatake T, Shibayama N, Park SY, Ishikawa T, Mustyakimov M, Fisher Z, Langan P, Morimoto Y, J Mol Biol. 2010 Apr 30;398(2):276-91. Epub 2010 Mar 15. PMID: 20230836 |
This OCA 
Structure page
uses Jmol,
developed by the Jmol Development Team
(documentation).