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<p>“Premodal structures” and “premodal algebras”, introduced in [5], are the result of an act of abstraction, just as monadic algebras, taken as starting point [5], are abstracted from functional monadic algebras introduced by P. R. Halmos [1].</p> <p>Here is proved that every premodal algebra is isomorphic to the abstract of a suitable concrete premodal algebra.</p>