Electronic transport properties of junctions between carbon nanotubes and graphene nanoribbons K.L. Ma, X.H. Yan, Y.D. Guo and Y. Xiao Eur. Phys. J. B, 83 4 (2011) 487-492 Published online: 24 October 2011 DOI: 10.1140/epjb/e2011-20313-9