1. Honsinger, C.W., Jones, P.W., Rabbani, M., Stoffel, J.C., Eastman Kodak Co, 2001. Lossless recovery of an original image containing embedded data. U.S. Patent 6,278,791. https://www.google.co.in/patents/US6278791.
2. Invertible authentication;Fridrich,2001
3. Distortion-free data embedding for images;Goljan,2001
4. Reversible data embedding using a difference expansion;Tian;IEEE Trans Circuits Syst Video Technol,2003
5. Reversible data hiding;Ni;IEEE Trans Circuits Syst Video Technol,2006