Critical quasiparticles in single-impurity and lattice Kondo models M. Vojta, R. Bulla and P. Wölfle Eur. Phys. J. Special Topics, 224 6 (2015) 1127-1146 Published online: 22 July 2015 DOI: 10.1140/epjst/e2015-02449-0