Liu Yang Baolong Guo Jianmin Lv A Modified Feature Based Image Watermarking Scheme in NSCT Domain. 67-70 2009 IAS http://dx.doi.org/10.1109/IAS.2009.339 conf/IEEEias/2009 db/conf/IEEEias/IEEEias2009.html#YangGL09