By discussing the properties of Cauchy-type integrals and Cauchy principal value integrals on the real axis in which kernel densities have singularities of higher order at ∞, we transform the singular integral equations on X with solutions having singularities of higher order at ∞ into ones along a closed contour with solutions having singularities of higher order. For the former we obtain the solutions and solvability conditions of the characteristic equations as well as the extended Noether theorem of complete equations by solving the latter.