Quantum properties of the codirectional three-mode Kerr nonlinear couplerF. A.A. El-Orany, M. Sebawe Abdalla and J. PeřinaEur. Phys. J. D, 33 3 (2005) 453-463DOI: https://doi.org/10.1140/epjd/e2005-00048-2