GD248B, The Coolest Known Helium Atmosphere White Dwarf
  This is to notify colleagues that our ApJ paper and corresponding astro-ph version are being withdrawn. Optical spectroscopy obtained with a 3m class telescope gave no indication of any features in the spectrum of 'GD248B' whatsoever. In addition to our proper motion data and optical photometry, all was consistent with our original interpretation for this object. However, very high SNR optical spectroscopy obtained at the Keck 10m revealed absorption features and points to a background subdwarf K7/M0 star moving at very high velocity with nearly identical proper motion to GD248, but alas, not a true companion and hence not a cool white dwarf. 
J. Farihi, E. E. Becklin, B. Zuckerman