Chunmei Liu Duoqian Miao Chunheng Wang Card Images Binarization Based on Dual-Thresholding Identification. 1158-1165 2008 ICIC (2) http://dx.doi.org/10.1007/978-3-540-85984-0_139 conf/icic/2008-2 db/conf/icic/icic2008-2.html#LiuMW08