3CTR:
reference: Crystal structure of the RRM domain of poly(A)-specific ribonuclease reveals a novel m(7)G-cap-binding mode., Monecke T, Schell S, Dickmanns A, Ficner R, J Mol Biol. 2008 Oct 17;382(4):827-34. Epub 2008 Jul 31. PMID: 18694759

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