Multi-frequency Wiener filtering of CMB data with polarization and   estimation of cosmological parameters
  We present a method of subtracting the foreground contamination for the measurement of CMB polarization. We calculate the resultant errors on CMB polarization and temperature-polarization cross correlation power spectra for the high frequency instrument (HFI) aboard Planck Surveyor, and estimate the corresponding errors on cosmological parameters. 
Simon Prunet, Shiv K. Sethi and Francois R. Bouchet