Some first-order theories of divisible ℓ-groups are well known, for example the theory of the totally ordered ones and the theories of the projectable ones , Lattice-ordered Groups, Kluwer Academic Press, Dordrecht, 1989, pp. 41–79). In this paper we study some theories of nonprojectable divisible ℓ-groups, the simplest example of which is . We introduce a generalization of the projectability property . We prove that the class of r-projectable special-valued divisible ℓ-groups is an elementary c…

Read moreSome first-order theories of divisible ℓ-groups are well known, for example the theory of the totally ordered ones and the theories of the projectable ones , Lattice-ordered Groups, Kluwer Academic Press, Dordrecht, 1989, pp. 41–79). In this paper we study some theories of nonprojectable divisible ℓ-groups, the simplest example of which is . We introduce a generalization of the projectability property . We prove that the class of r-projectable special-valued divisible ℓ-groups is an elementary class and give a classification of its completions