(39.1): J.N. Lier, Thesis, Amsterdam, 1939.

(42.1): J.R. MacNally, Jr., G.R. Harrison and H.B. Park, J. opt. Soc. Am., 1942, 32, 334-47.

(43.1): T.L. De Bruin, P. Schuurmans and P.F.A. Klinkenberg, Z. Physik, Dtsch., 1943, 121, 667-78.

(44.1): T.L. De Bruin, P.F.A. Klinkenberg and P. Schuurmans, Z. Physik, Dtsch., 1944, 122, 23-35.

(45.1): J.R. MacNally, Jr., J. opt. Soc. Am., 1945, 35, 390-8.

(46.3): P. Schuurmans, Thesis, Amsterdam, 1946.

(53.1): G.L. Stukenbroeker and J.R. MacNally, Jr., J. opt. Soc. Am., 1953, 43, 36-43.

(58.1): G.W. Charles, 1958, Report O.R.N.L. 2319.

(60.5): E.A. Vernyi and V.N. Egorov, Optika Spektrosk., S.S.S.R., 1960, 9, 692-702 (trad.: Optics Spectr., U.S.S.R., U.S.A., 1960, 9, 367-71).

(69.3): N. Minsky, Thesis, Jerusalem, 1969.

(74.6): S. Gerstenkorn, P. Luc, J. Vergès, D.W. Englekemeir, J.E. Gindler and F. S. Tomkins, J. Physique, Fr., 1974, 35, 483-95.

(74.9): R. Zalubas and C.H. Corliss, J. Res. nat. Bur. Stand. A, USA, 1974, 78, 163-246.

(83.9): B.A. Palmer and R. Englemart, Jr., 1983, Report L.A. - 9615.

(84.3): R. Engleman, Jr. and B.A. Palmer, J. opt. Soc. Am. B, 1984, 1, 782-7.

(unp.2): J. Blaise.

(unp.18): R. Engleman, Jr.