2M18:
reference: Structure of Human Telomeric RNA (TERRA): Stacking of Two G-Quadruplex Blocks in K(+) Solution., Martadinata H, Phan AT, Biochemistry. 2013 Apr 2;52(13):2176-83. doi: 10.1021/bi301606u. Epub 2013 Mar, 19. PMID: 23445442

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