2IBP:
reference: Discovery of a thermophilic protein complex stabilized by topologically interlinked chains., Boutz DR, Cascio D, Whitelegge J, Perry LJ, Yeates TO, J Mol Biol. 2007 May 18;368(5):1332-44. Epub 2007 Mar 6. PMID: 17395198

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