1. Blanco, V.M., Demers, S.; Douglass, G.G., Fitzgerald, M.P. 1968, Publ. U.S. Naval Obs., 2-d series, 21
2. Ferrer, L., Jaschek, C. 1971, Publ. Astron. Soc. Pacific 83,346
3. Hubert-Delplace, A.M., Hubert, H., 1979 “Un Atlas des Etoiles Be” Observatoire de Paris-Meudon and Observatoire de Haute-Provence
4. Jaschek, M., Hubert-Delplace, A.M., Hubert, H., Jaschek, C. 1980, Astron, and Astrophys. Suppl. Ser. 42,103