
"For example, presses (with barbell, dumbbells, or machine) and flyes performed on an incline bench will isolate stress on the upper pecs.
The same movements done on a decline bench isolate stress on the lower and outer pectorals. And to place maximum stress on the inner pecs, you can do pec-deck flyes and narrow-grip bench presses. The accumulation of movements performed from a variety of angles will ultimately give you perfect pectoral development."
Arnold's encyclopedia concurs with Joe's along with pretty much any bodybuilding reference you can find. I challenge anyone to find an authoritative source that lists declines as a specific upper or middle pectoral development exercise.
The OP is specifically asking for exercises that "focus" on upper and mid chest. Decline doesn't. We most certainly can and should focus on different parts of our muscles if they are lagging. To say you can't or that it's not possible is just not true.
Sorry for all the different fonts...couldn't get them to match.
The URL for the website that references the weider excerpt is here.
http://www.bodybuilding.com/fun/pecs.htm