Szukana fraza: [Abstract = "An investigation is made on the effect of Hall currents on thermal instability of a compressible couple\-stress fluid in the presence of a horizontal magnetic field saturated in a porous medium. The analysis is carried out within the framework of the linear stability theory and normal mode technique. A dispersion relation governing the effects of viscoelasticity, Hall currents, compressibility, magnetic field and porous medium is derived."]