1. J A Giordmaine and R C Miller,Phys. Rev. Lett. 14, 973 (1965);Appl. Phys. Lett. 9, 298 (1966)
2. For various research activities on optical parametric oscillators see, for example, the references in the feature issue (September and November) on Optical Parametric Oscillation and Amplification,J. Opt. Soc. Am. B10, 1656 (1993)
3. For a review of the optical parametric oscillators see, for example, R L Byer inTreatise in quantum electronics edited by H Rabin and C L Tang (New York, Academic, 1973), p. 588–702
4. R J Smith, inAdvances in Lasers edited by A K Levine and A J deMaria (New York, Dekker 1976) vol. 4
5. F Zernike and J E Midwinter,Applied nonlinear optics (New York, Wiley, 1973) p. 153–176