****************************************************** PR # 41146 3C279 is a typical OVV quasar with high variability in radio through GeV-gamma-ray, and the brightest GeV-gamma-ray AGN. The property in radio to X-rays will strongly support the SSC model. However, bright GeV-gamma-ray flux by CGRO cannot be simply explained by this model. The research of GeV-gamma-ray emission mechanism unknown is expected to lead the origin of blazar activity, like as jets and relativistic electron production. We would propose the ASCA monitoring observation of 3C279 simultaneously with CGRO/EGRET, ROSAT, IUE and the other multifrequency observatries, which is the final chance of EGRET observation. We expect to obtain the fine correlation between the brightness in GeV-gamma-rays and X-rays, which is a key of the research of the GeV-gamma-ray emission. ******************************************************