LAGEOS-type Satellites in Critical Supplementary Orbit Configuration and   the Lense-Thirring Effect Detection
  In this paper we analyze quantitatively the concept of LAGEOS--type satellites in critical supplementary orbit configuration (CSOC) which has proven capable of yielding various observables for many tests of General Relativity in the terrestrial gravitational field, with particular emphasis on the measurement of the Lense--Thirring effect. 
Lorenzo Iorio, David M. Lucchesi