5G4V: Association Of Four Two-K-Turn Units Based On Kt-7 3bg,3nc, Forming A Square-Shaped Structure
reference: A quasi-cyclic RNA nano-scale molecular object constructed using kink turns., Huang L, Lilley DM, Nanoscale. 2016 Aug 18;8(33):15189-95. doi: 10.1039/c6nr05186c. PMID: 27506301

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