1MGR:
reference: X-ray structure of two crystalline forms of a streptomycete ribonuclease with cytotoxic activity., Sevcik J, Urbanikova L, Leland PA, Raines RT, J Biol Chem 2002 Dec 6;277(49):47325-30. Epub 2002 Sep 11. PMID: 12228255

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