1. R.C. Elton: Appl. Opt. 14, 97 (1975)
2. A.V. Vinogradov, I.I. Sobelman, E.A. Youkov: Sov. J. Quantum. Electron. 7, 32 (1975)
3. D.L. Matthews, P.L. Hagelstein, M.D. Rosen, M.J. Eckart, N.M. Ceglio, A.U. Hazi, H. Medecki, B.J. McGowan, J.E. Trebes, B.L. Whitten, E.M. Campbell, C.W. Hatcher, A.M. Hawryluk, R.L. Kauffman, L.D. Pleasance, G. Rambach, J.H. Scofield, G. Stone, T.A. Weaver: Phys. Rev. Lett. 54, 110 (1985)
4. D.J. Keane, J.L. Bourgade, P. Combis, R.A. London, M. Louis-Jacquet, B.J. McGowan, D.L. Matthews, D. Naccache, O. Peyrusse, M.D. Rosen, G. Thiell, B.L. Whitten: OSA Proceedings on Short Wavelength Coherent Radiation: Generation and Applications, ed. by R.W. Falcone, J. Kirz (Optical Society of America, Washington DC (1988), Vol. 2, p. 93
5. T.N. Lee, E.A. McLean, R.C. Elton: Phys. Rev. Lett. 59, 1185 (1987)