184D:
reference: Self-association of a DNA loop creates a quadruplex: crystal structure of d(GCATGCT) at 1.8 A resolution., Leonard GA, Zhang S, Peterson MR, Harrop SJ, Helliwell JR, Cruse WB, d'Estaintot BL, Kennard O, Brown T, Hunter WN, Structure 1995 Apr 15;3(4):335-40. PMID: 7613864

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