5DZU:
reference: Structure of a Kunitz-type potato cathepsin D inhibitor., Guo J, Erskine PT, Coker AR, Wood SP, Cooper JB, J Struct Biol. 2015 Dec;192(3):554-60. doi: 10.1016/j.jsb.2015.10.020. Epub 2015 , Nov 2. PMID: 26542926

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