4AVS:
reference: Interaction of serum amyloid P component with hexanoyl bis(D-proline) (CPHPC)., Kolstoe SE, Jenvey MC, Purvis A, Light ME, Thompson D, Hughes P, Pepys MB, Wood SP, Acta Crystallogr D Biol Crystallogr. 2014 Aug 1;70(Pt 8):2232-40. doi:, 10.1107/S1399004714013455. Epub 2014 Jul 25. PMID: 25084341

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