A unified approach to the fast computation of all discrete trigonometric transforms. - Okan K. Ersoy; Neng-Chung Hu (ICASSP, 1987)

Fast algorithms for the real discrete Fourier transform. - Okan K. Ersoy; Neng-Chung Hu (ICASSP, 1988)

Fast algorithms for the discrete Fourier preprocessing transforms. - Okan K. Ersoy; Neng-Chung Hu (IEEE Trans. Signal Process., 1992)

Generalized discrete Hartley transforms. - Neng-Chung Hu; Hong-I Chang; Okan K. Ersoy (IEEE Trans. Signal Process., 1992)

Fast algorithms for the recursive computation of two-dimensional discrete cosine transform. - Wen-Hsien Fang; Neng-Chung Hu; Shih-Kuo Shih (EUSIPCO, 1998)