4ABW:
reference: Crystallographic Study of Novel Transthyretin Ligands Exhibiting Negative-Cooperativity between Two Thyroxine Binding Sites., Tomar D, Khan T, Singh RR, Mishra S, Gupta S, Surolia A, Salunke DM, PLoS One. 2012;7(9):e43522. Epub 2012 Sep 4. PMID: 22973437

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