A BRIGHTEST CLUSTER GALAXY WITH AN EXTREMELY LARGE FLAT CORE. - Postman, Marc; Lauer, Tod R.; Donahue, Megan; Graves, Genevieve; Coe, Dan; Moustakas, John; Koekemoer, Anton; Bradley, Larry; Ford, Holland C.; Grillo, Claudio; Zitrin, Adi; Lemze, Doron; et al. (Astrophysical Journal, 2012)