1. http://www.patents.ibm.com/ http://www.patents.ibm.com/
2. http://www.comm.loreonto.edu.`deepa/wtmk.html http://www.comm.loreonto.edu.`deepa/wtmk.html
3. http://www.itd.nrl.navy.muil.itd5540/ieee/cipher/ readers-guide/journals.html http://www.itd.nrl.navy.muil.itd5540/ieee/cipher/ readers-guide/journals.html
4. http://www.cosimi.die.unifi.it/~priva/watermakking/ http://www.cosimi.die.unifi.it/~priva/watermakking/
5. 3-D watermarking: http://www.tribm.co.jp/projects/s7340/ embed/idms/idms.htm 3-D watermarking: http://www.tribm.co.jp/projects/s7340/ embed/idms/idms.htm