%0 Journal Article %T A combinatorial approach to rational exponential groups %A M. Shahryari %J Mathematics %D 2013 %I arXiv %X We give a suitable definition of the concept of rational complex and prove that every rational exponential group is the fundamental group of some such a complex. In this framework, we prove that the variety of rational exponential groups is a Schreier variety. %U http://arxiv.org/abs/1308.3452v4