Abstract:In this paper we have given the construction of free $\ell $-groups generated by a po-group and the construction of free products in any sub-product class $\Cal U$ of $\ell $-groups. We have proved that the $\Cal U$-free products satisfy the weak subalgebra property.
Keywords: lattice-ordered group ($\ell $-group), free $\ell $-group, free product of $\ell $-groups, sub-product class of $\ell $-groups
AMS Subject Classification: 06F15