Reference:
  Author: Jane S. Richardson and Bohdan Schneider and Laura W. Murray and Gary J. Kapral and Robert M. Immormino and Jeffrey J. Headd and David C. Richardson and Daniela Ham and Eli Hershkovits and Loren Dean Williams and Kevin S. Keating and Anna Marie Pyle and David Micallef and John Westbrook and Helen M. Berman
  Title: "RNA backbone: Consensus all-angle conformers and modular string nomenclature (an RNA Ontology Consortium contribution)"
  Journal: RNA
  Year: 2008
  Volume: 14
  Number: 3
  Pages: 465-481
  DOI: 10.1261/rna.657708
  PMID: 18192612
  URL: http://rnajournal.cshlp.org/content/14/3/465
  eprint: http://rnajournal.cshlp.org/content/14/3/465.full.pdf+html
