Let H be the cartesian product of a family finite abelian groups indexed by set Ω. A given poset (i.e., partially ordered set) P = (Ω, ≼P) gives rise to metric on H, which further leads partition Q(H, P) H. We prove that if is Fourier-reflexive, then its dual Λ coincides with Ĥ induced P, and moreover, necessarily hierarchical. This result establishes conjecture proposed Gluesing-Luerssen in [5...