  We have shown in previous work that the equivalence of the Heisenberg and
Schr\"odinger pictures of quantum mechanics requires the use of the Born and
Jordan quantization rules. In the present work, we give further evidence that
the Born--Jordan rule is the correct quantization scheme for quantum mechanics.
For this purpose, we use correct short-time approximations to the action
functional, which lead to the desired quantization of the classical
Hamiltonian. We thus prove that a previous argument of Kerner and Sutcliffe,
refuted by Cohen, is correct.
