Title: Polysuperharmonic functions on a harmonic space
Abstract: In the context of the axiomatic potential theory, we introduce the notions of polyharmonic functions and polypotentials on a Brelot harmonic space $\Omega$. For these functions,we prove some results analogous to the Riesz decomposition, balayage, domination principle, etc., which are usually associated with harmonic and superharmonic functions on $\Omega$. We also consider the polyharmonic classifications of the harmonic spaces.