1RPA:
reference: Three-dimensional structure of rat acid phosphatase in complex with L(+)-tartrate., Lindqvist Y, Schneider G, Vihko P, J Biol Chem 1993 Oct 5;268(28):20744-6. PMID: 8407898

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