4B4H:
reference: The Structure of a Bacterial Cellobiohydrolase: The Catalytic Core of the Thermobifida fusca Family GH6 Cellobiohydrolase Cel6B., Sandgren M, Wu M, Karkehabadi S, Mitchinson C, Kelemen BR, Larenas EA, Stahlberg J, Hansson H, J Mol Biol. 2013 Feb 8;425(3):622-35. doi: 10.1016/j.jmb.2012.11.039. Epub 2012, Dec 5. PMID: 23220193

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