TECHNICAL REPORT OF IEICE (INSTITUTE OF ELECTRONICS, INFORMATION AND COMMUNICATION ENGINEERS OF JAPAN), page. 33 - 41, 1993-10
ELECTRONICS LETTERS, vol. 29, no. 14, page. 1281 - 1282, 1993-07-08
JOURNAL OF VISUAL COMMUNICATION AND IMAGE REPRESENTATION, vol. 4, no. 1, page. 39 - 45, 1993-03