 Other recent interpretations of Bohr’s correspondence principle include Robert Batterman’s, according to which “the CP is a statement to the effect that the radiative processes to which the second postulate \([h\nu = E' - E'']\) applies are ‘correlated’ with, or ‘correspond’ to, mechanical vibrations or periodic motions of the charged particles, the electrons, in the atom” (Batterman 1991, p. 203). Batterman rightly notes that the correspondence principle is not the claim that quantum mechanics must contain classical mechanics as a limiting case, and argues that the asymptotic agreement of classical and quantum frequencies (the frequency interpretation) is not the correspondence principle, but rather something that is justified and explained by the correspondence principle.