Abstract
The combined effect of the solar radiation pressure and the oblateness of the planets on the position and stability of the Lagrangian points within the restricted elliptic three-body problem was studied. We found that the solar radiation pressure and planet oblateness slightly changed the location of the Lagrangian points. New formulas for the location of the collinear points using the Lagrange inversion method were introduced. For large values of the force ratio B; the ratio between the solar radiation force and the gravitational attraction force due to the Sun; we found that the collinear point L-3 is stable.