6DZC:
reference: A Small Cyclic beta-Hairpin Peptide Mimics the Rbfox2 RNA Recognition Motif and Binds to the Precursor miRNA 20b., Sun YT, Shortridge MD, Varani G, Chembiochem. 2019 Apr 1;20(7):931-939. doi: 10.1002/cbic.201800645. Epub 2019 Feb, 15. PMID: 30537200

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