Port, starboard, midships and aft are mentioned, being mentioned means they are there. Where exactly is the question for those phasers. You, I believe, brought up they were mentioned in dialogue.
TAS would seem to be canon, or at least reference material; or "Questionable Canon" as Memory Alpha puts it in the links previously provided.
However, In A Mirror, Darkly only showed the ventral phasers and the aft phasers providing dorsal shots. The Defiant in that episode even tilts to one side to fire torpedoes at the ship attacking her dorsal side. If there was ever a time for dorsal phasers on the saucer to fire, that would have been the time.
So yes, where are the emitters?