ILC, and TCM. However, we cannot conclude that the non-Gaussian signatures are free from the effect of foreground contamination. The $\Delta g$ and $A_{-/+}^N - A_{-/+}^S$ decrease as the higher Galactic cut is applied, though their dependence on the Galactic cut is weak.

Second, the non-Gaussianity can appear due to the Integrated Sachs-Wolfe (ISW) and the Sunyaev-Zel’dovich (SZ) effects. The large-scale structures, which intersect the paths of CMB photons, can affect the primary CMB anisotropy. In a $\Lambda$-dominated CDM universe, the CMB anisotropies are expected to be correlated with matter density fluctuations at $z \la 2$ through the ISW effect (Crittenden & Turok 1996). Nolta et al. (2003) have detected cross-correlation of the NRAO VLA Sky Survey radio source catalog with the WMAP data. Boughn & Crittenden (2003), Fosalba & Gaztañaga (2003), Fosalba, Gaztañaga, & Castander (2003), and Scranton et al. (2003) have reported that there exists a correlation between the WMAP temperature anisotropy and the galaxy distribution. Diego, Silk, & Sliwa (2003) estimate the cross-power spectrum between the WMAP CMB and the ROSAT X-ray maps, and did not find any significant correlation between two data sets. The SZ clusters appear in arcminute scales and the angular resolution and the 