“…There have been numerous studies of group-valued measures on Boolean algebras, orthomodular lattices, and their generalizations (Avallone and Hamhalter, 1996;D'Andrea and De Lucia, 1992;De Lucia and Morales, 1998;García Mazarío, 2001;Göbel et al, 1996;Navara et al, 1993;Bhashkara Rao and Shortt, 1991). Additionally, the group-valued measures on an orthomodular structure L are closely linked to the unigroup of L, a key ingredient in David Foulis' recent algebraic approach to non-commutative measure theory (Bennett and Foulis, 1997;Foulis et al, 1998;Foulis, 2000).…”