This article is from the Blues Brothers FAQ, by Glen Pringle firstname.lastname@example.org with numerous contributions by others.
The Girl from Ipanema.
This is an in joke which John Landis uses in many of his movies,
such as in "Spies like Us" where it is made to look like a
recruiters poster on a wall.
The other in joke is the movie title "See You Next Wednesday" which
is on the billboard that the cops are hiding behind and is used in
other movies such as "An American Werewolf in London."