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There is a simple way of defining certain L languages as unique minimal solutions of language equations. For instance, the language generated by a DTOL system with axiom P and tables (endomorphisms) delta1,...,deltam is also the unique minimal solution of the equation X=delta1(X)+...+deltam(X)+(P). One may also consider systems of such equations which has the effect of adding a regular control on the use of tables and adding more axioms. The unique minimal solutions of such systems are easily seen to be n-tuples of ETOL languages. This note proves that the unique maximal solutions of these systems are n-tuples of ETOL languages, too. It also gives a characterization of all solutions of such a system by extracting a family of n-tuples of ETOL languages the (componentwise) union closure of which (including infinite unions) equals the family of all solutions of the system.