Presented at 2015 Spring Meeting of Acoustical Society of Japan (domestic conference) 北村大地, 小野順貴, 澤田宏, 亀岡弘和, 猿渡洋, "過決定条件BSS におけるランク1 空間制約の緩和," 日本音響学会 2015年春季研究発表会, 3-10-11, pp.629-632, Tokyo, March 2015. Daichi Kitamura, Nobutaka Ono, Hiroshi Sawada, Hirokazu Kameoka, Hiroshi Saruwatari, "Relaxation of rank-1 spatial model in overdetermined BSS," Proceedings of 2015 Spring Meeting of Acoustical Society of Japan, 3-10-11, Tokyo, March 2015 (in Japanese).