Justo Miranda said:
Hagelkorn based 1946 french desing with die-cast concrete wings
According to "Les Avions Bréguet 1940-1971" (Jean Cuny et Pierre Leyvastre, DOCAVIA, 1977), the wings were made of a material rather like a composite material with steel wires as fibers and concrete as matrix.
Six Br 910 gliding bombs were tested in 1952-53.