3HVP:
reference: Conserved folding in retroviral proteases: crystal structure of a synthetic HIV-1 protease., Wlodawer A, Miller M, Jaskolski M, Sathyanarayana BK, Baldwin E, Weber IT, Selk LM, Clawson L, Schneider J, Kent SB, Science 1989 Aug 11;245(4918):616-21. PMID: 2548279

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