2MNC:
reference: NMR Characterization of an Oligonucleotide Model of the MiR-21 Pre-Element., Chirayil S, Wu Q, Amezcua C, Luebke KJ, PLoS One. 2014 Sep 24;9(9):e108231. doi: 10.1371/journal.pone.0108231., eCollection 2014. PMID: 25250627

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