by Rettori, C., Davidov, D., Suassuna, J., Barberis, G.E., Elschner, B., Born, D.
Published in Solid state communications (01.01.1978)

by Vaknin, D., Davidov, D., Nieuwenhuys, G.J., Hoekstra, F.R., Barberis, G.E., Mydosh, J.A.
Published in Physica B + C (01.08.1981)

by Suassuna, J.F., Rettori, C., Vargas, H., Barberis, G.E., Hennies, C.E., Oliveira, N.F.
Published in The Journal of physics and chemistry of solids (01.01.1977)