1. Abhayapala, T.D., Ward, D.B.: Theory and design of high order sound field microphones using spherical microphone array. In: Proceedings of the IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), vol. 2, pp. 1949–1952 (2002). doi: 10.1109/ICASSP.2002.1006151
2. Abramowitz, M., Stegun, I.A. (eds.): Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables. Dover Publications, New York (1972)
3. Benesty, J., Chen, J., Huang, Y.: Microphone Array Signal Processing. Springer, Berlin (2008)
4. Brandstein, M.S., Ward, D.B. (eds.): Microphone Arrays: Signal Processing Techniques and Applications. Springer, Berlin (2001)
5. Brandwood, D.H.: A complex gradient operator and its application in adaptive array theory. Proc. IEEE 130(1, Parts F and H), 11–16 (1983)