Peřina, J., Centini, M., Sibilia, C., Bertolotti, M. Photon-pair generation in random nonlinear layered structures. Physical Review A. 2009, 80(3), 033844/1-033844/10. ISSN 1050-2947. E-ISSN 2469-9934. Available: https://doi.org/10.1103/PhysRevA.80.033844