1. BERLAND (G.) French patent n° 635.283(1927)
2. stationary concentrating reflector;STEWARD;Appl. Optics,1975
3. MEINEL (A.B.), McKENNEY (D.B.) Colloque “Solar Electricity” (Toulouse 1–5 mars 1976, CNES (Department des Affaires Universitaires), Edit. Toulouse 1976 P. 876.
4. Applied solar energy;MEINEL,1976
5. AUTHIER (B.), French paten n° 76/28550(1976)