Lab . http://www.lbl.gov/Science-Articles/Archive/MSD-superconductor-Cohen-Louie.html . Retrieved 12 March 2012 .   ^ A. F. Hebard et al. (1991). "Superconductivity at 18 K in potassium-doped C 60 ". Nature 350 (6319): 600. Bibcode 1991Natur.350..600H . doi : 10.1038/350600a0 .   ^ A. Y. Ganin et al. (2008). "Bulk superconductivity at 38 K in a molecular