Let be an formula, where and is the language of ordered rings . Then there are and such that is equivalent to
References
Marker, D. ``Model Theory and Exponentiation.'' Not. Amer. Math. Soc. 43, 753-759, 1996.
Wilkie, A. J. ``Model Completeness Results for Expansions of the Ordered Field of Real Numbers by
Restricted Pfaffian Functions and the Exponential Function.'' J. Amer. Math. Soc. 9, 1051-1094, 1996.