is the velocity of the Sun with respect to the centroids of stellar groups; l and b are the Galactic longitude and latitude of the Solar apex; 
1, 2 and 3 are the major, mean, and minor emi-axes of the velocity allipsoid, which can be considered equal to the velocity dispersions u,v, and w, respectively; L1 and B1 are the longitude and latitude component of the vertex deviation; <e> is the mean eccentricity; <Zmax> is the mean maximum orbital radius; n0 is the number density of F2-G2 stars in the disk plane.
VERTICAL STRUCTURE OF THE GALACTIC DISK. Velocity ellipsoid parameters, orbital elements, and number densities in the Galactic plane for four groups of F2-G2stars.discussion in the text