Yasuhiko Okuma and Yuichi Suzuki and Takahiro Murakami and Yoshihisa Ishida, A Fast Directionally Constrained Minimization of Power Algorithm for Extracting a Speech Signal Perpendicular to a Microphone Array. journal = {International Journal of Electronics and Communication Engineering}, [online]. World Academy of Science, Engineering and Technology. January 2007, vol. 1(1). 19 - 24 [viewed 19 April 2024]. Available from: https://publications.waset.org/pdf/6228.