One, the Ernst Lubitsch movie, Trouble in Paradise, derives from a play by the Laszlo Aldadar, The Honest Finder. The other, She Loves Me, a musical on stage at the Ashland Shakespeare Festival, dervies from another playwright--this one Miklós László. Miklós, in addition to all those acute accents, gets his own Wiki page; no such luck for Aladar.
She Loves Me is perhaps the latest in a whole string of knockoffs, notably Lubitsch's 1940 Shop Around the Corner and the Hanks/
I leave it for graduate students to chart all the points of convergence and comparison.