4XFW:
reference: Structure of alpha-carbonic anhydrase from the human pathogen Helicobacter pylori., Compostella ME, Berto P, Vallese F, Zanotti G, Acta Crystallogr F Struct Biol Commun. 2015 Aug 1;71(Pt 8):1005-11. doi:, 10.1107/S2053230X15010407. Epub 2015 Jul 28. PMID: 26249690

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