The Search for Brown Dwarfs around White Dwarfs
  The infrared search for substellar companions to nearby white dwarfs has been going for a little more than a decade. The most recent phase has been a wide field proper motion search carried out primarily at Steward Observatory, where we are complete down to J=18. Earlier phases included near field searches at the IRTF and Keck Observatory. In the last year we have discovered ten previously unrecognized faint proper motion companions. Of the recent discoveries, most are white dwarfs and a few M dwarfs. GD165B, discovered in 1988 as part of our program, is still the only known companion to a white dwarf with spectral type later than M. 
J. Farihi, E.E. Becklin, B. Zuckerman