  In this letter we further analyze the concept of the use of a pair of
identical geodetic satellites placed in identical orbits except for the
inclinations which should be supplementary for measuring the Lense-Thirring
effect in the terrestrial gravitational field. It turns out that not only the
sum of the nodes, as already proposed for the LAGEOS-LARES mission, but also
the difference of the perigees could be fruitfully adopted.
