1HDF:
reference: Crystal structure of the calcium-loaded spherulin 3a dimer sheds light on the evolution of the eye lens betagamma-crystallin domain fold., Clout NJ, Kretschmar M, Jaenicke R, Slingsby C, Structure (Camb) 2001 Feb 7;9(2):115-24. PMID: 11250196

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