A Note on The Existential Theory of Equations in Plain Groups.

Volker Diekert Markus Lohrey A Note on The Existential Theory of Equations in Plain Groups. 1-7 2002 12 IJAC 1-2 http://dx.doi.org/10.1142/S0218196702000870 db/journals/ijac/ijac12.html#DiekertL02