An investigation of doubly-resonant optical parametric oscillators and nonlinear crystals for squeezing
M. Stefszky, C.M. Mow-Lowry, K. McKenzie, S. Chua, B.C. Buchler, T. Symul, D.E. McClelland, P.K. Lam, Journal of Physics B: Atomic, Molecular and Optical Physics (2010).