1. J.W. Goodman:Introduction to Fourier Optics (McGraw-Hill, San Francisco 1968) p. 167
2. E. Kreyszig:Advanced Engineering Mathematics (John Wiley and Sons, Inc., New York 1968) pp. 506–508
3. For the details of filter fabrication, please refer to the Ph.D. thesis completed by D.P. Jablonowski at Carnegie-Mellon University (1973)
4. A. Carlson, G. Hannauer, T. Carey, P.J. Holsber (Eds.):Handbook of Analog Computation (Electronic Associates, Inc., Princeton, N. J. 1967)