  In tagged cascade decays of the type P^0 (P^0-bar) -> M^0 / M^0-bar X -> f X
there are two complex CPT-violating parameters: one in P^0 - P^0-bar mixing,
the other one in M^0 - M^0-bar mixing. I analyze those decays and find that, in
principle, the former parameter can be extracted from a careful comparison of
their time dependences. CPT violation in M^0 - M^0-bar mixing, on the other
hand, always appears entangled with ratios of decay amplitudes and cannot be
extracted.
