1FMB:
reference: Structure of equine infectious anemia virus proteinase complexed with an inhibitor., Gustchina A, Kervinen J, Powell DJ, Zdanov A, Kay J, Wlodawer A, Protein Sci 1996 Aug;5(8):1453-65. PMID: 8844837

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