References
- Aho , A.V. , Hopcroft , J.E. and Uuman , J.D. 1974 . The Design and Analysis of Computer Algorithms , Reading, Mass : Addison-Wesley .
- Amir , A. and Choueka , Y. 1981 . Loop programs and polynomially computable functions . International Computer Math , A 9 : 195 – 205 .
- Brainerd , W.S. and Landweber , L.H. 1974 . Theory of Computation , New York : Wiley .