137D:
reference: Evidence for crystal environment dominating base sequence effects on DNA conformation: crystal structures of the orthorhombic and hexagonal polymorphs of the A-DNA decamer d(GCGGGCCCGC) and comparison with their isomorphous crystal structures., Ramakrishnan B, Sundaralingam M, Biochemistry 1993 Oct 26;32(42):11458-68. PMID: 8218212

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