Having analyzed Fernandez's approach for the Morse oscillator with a k
inetic coupling [Phys. Lett. A 229 (1997) 262] and contrasting it with
our original paper [Phys. Lett. A 213 (1996) 226], we point out that
a new representation is implicitly used by Fernandez. The dynamic phas
e difference of two wave functions obtained via two different approach
es is due to different representations adopted in these two papers res
pectively. (C) 1997 Elsevier Science B.V.