4JJR:
reference: A monoclinic crystal form of casein kinase 1 delta, Zeringo NA, Murphy L, McCloskey EA, Rohal L, Bellizzi JJ 3rd, Acta Crystallogr Sect F Struct Biol Cryst Commun. 2013 Oct 1;69(Pt 10):1077-1083., Epub 2013 Sep 28. PMID: 24100552

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