reserve G for Group,
  a,b for Element of G,
  m, n for Nat,
  p for Prime;

theorem
  for G being strict finite Group st G is p-group &
  expon (G,p) = 0 holds G is p-commutative-group
proof
  let G be strict finite Group;
  assume
A1:G is p-group & expon (G,p) = 0;
  then G = (1).G by Th24;
  hence thesis by A1;
end;
