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<http://chemwiki.ucdavis.edu/Wikitexts/Diablo_Valley_College/DVC_Chem_227%3A_Rusay/Chemwiki/Nucleosides>
<http://chemwiki.ucdavis.edu/Wikitexts/Diablo_Valley_College/DVC_Chem_227%3A_Rusay/Chemwiki/Nucleosides>