1APN:
reference: Crystallographic structure of metal-free concanavalin A at 2.5 A resolution., Bouckaert J, Loris R, Poortmans F, Wyns L, Proteins 1995 Dec;23(4):510-24. PMID: 8749847

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