Y. S. Kavian, W. Ren, M. Naderi, M. S. Leeson, and E. L. Hines, “Fault Tolerant Dense Wavelength Division Multiplexing Optical Transport Networks”, JTIT, vol. 35, no. 1, pp. 63–67, Mar. 2009, doi: 10.26636/jtit.2009.1.916.