% SZS status Theorem for plus__ass
% SZS output start Proof for plus__ass
  file('i/f/ring/plus__assoc',ch4s_rings_plusu_u_assoc)).
  file('i/f/ring/plus__assoc',ah4s_rings_isu_u_ringu_u_def)).
% SZS output end Proof for plus__ass
