Word problems requiring exponential time(Preliminary Report)

L. J. Stockmeyer, A. R. Meyer
1973 Proceedings of the fifth annual ACM symposium on Theory of computing - STOC '73  
doi:10.1145/800125.804029 dblp:conf/stoc/StockmeyerM73 fatcat:mvddf6q2ujcvtd4k5k2mctgvk4