I picked up these covers recently and researching them for my reference. I noticed the listing in TGT that stated "Copenhagen Bar, 2140 Prater Way, open 1989, closed no" Clearly the age of these cover places them earlier. So I citysearched the place, got a # and a very helpful bartender who knew the history.
Opened in 1949 at the address seen on the matchcovers (2620 Prater Way) then in 1963 moved to its current local at 2140 Prater Way. The family owned business was passed down from "Bear" to his son in the late 80's. I thought it was interesting