86 GHz SiO maser survey of late-type stars in the Inner Galaxy III.   Interstellar extinction and colours of the SiO targets
  We have determined extinction corrections for a sample of 441 late-type stars in the inner Galaxy, which we previously searched for SiO maser emission, using the 2MASS near-infrared photometry of the surrounding stars. From this, the near-infrared extinction law is found to be approximated by a power law A$_\lambda \propto \lambda^{-1.9\pm0.1}$. Near- and mid-infrared colour-colour properties of known Mira stars are reviewed. From the distribution of the dereddened infrared colours of the SiO target stars we infer mass-loss rates between $10^{-7}$ and $10^{-5}$ M$_\odot$ yr$^{-1}$. 
M. Messineo, H. J. Habing, K. M. Menten, A. Omont, L. O. Sjouwerman   and F. Bertoldi