2BCA:
reference: High-resolution structure of calcium-loaded calbindin D9k., Kordel J, Skelton NJ, Akke M, Chazin WJ, J Mol Biol 1993 Jun 5;231(3):711-34. PMID: 8515447

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