1. Lect Notes Comput Sci;D. Aucsmith,1996
2. Lect Notes Comput Sci;D. Boneh,1995
3. C. Collberg and C. Thomborson. On the limits of software watermarking. Technical Report 164, Department of Computer Science, the University of Auckland, Auckland, New Zealand, 1998.
4. Lect Notes Comput Sci;I. C. J. Kilian,1996
5. M. Garey and D. S. Johnson. Computers and Intractability: A Guide to the Theory of NP-Completeness. Freeman, 1979.