Local superconducting density of states of ErNi2B2C
  We present local tunnelling microscopy and spectroscopy measurements at low temperatures in single crystalline samples of the magnetic superconductor ErNi2B2C. The electronic local density of states shows a striking departure from s-wave BCS theory with a finite value at the Fermi level, which amounts to half of the normal phase density of states. 
M. Crespo, H. Suderow, S. Vieira, S. Bud'ko, P.C. Canfield