@misc{cryptoeprint:1999:024, author = {M. Bellare and R. Impagliazzo}, title = {A tool for obtaining tighter security analyses of pseudorandom function based constructions, with applications to PRP to PRF conversion }, howpublished = {Cryptology ePrint Archive, Report 1999/024}, year = {1999}, url = {http://eprint.iacr.org/1999/024}, }