Classifying Luyten Stars Using An Optical-Infrared Reduced Proper Motion   Diagram
  We present a V-J reduced proper motion (RPM) diagram for stars in the New Luyten Two-Tenths (NLTT) catalog. In sharp contrast to the RPM diagram based on the original NLTT data, this optical-infrared RPM diagram shows distinct tracks for white dwarfs, subdwarfs, and main-sequence stars. It thereby permits the identification of white-dwarf and subdwarf candidates that have a high probability of being genuine. 
Samir Salim and Andrew Gould (Ohio State University)