Here is my collection of Paul Lothar Muller prints. I believe they are from the 1930s/1940s.
"May Time Airs" (unframed)
"Singing Lesson Try, Try Again" (unframed)
"Singing Lessons" (framed)
Gnome with Flute (framed)
Gnome with Accordion
Gnome with Guitar
Gnome Doctor with Rabbit
Paul Lothar Muller print Gnome with Birds Printed in Germany Copyright by Kunstverlag Fingerle & Co., Esslingen a.N.
Paul Lothar Muller Gnome with Frog Print Printed in Germany Copyright by Kunstverlag Fingerle & Co., Esslingen a.N.
Two Alfred Schonian Jig Puzzles by Marlboro 1930s?
Alfred Schonian "Fishing for Rainbows"
Alfred Schonian
Vintage Calender top advertisement found at a local flea market.
Gnome Calender Ad.
A Vintage German Child’s Stationary Set.
Child's Stationary Set
Raggedy Ann’s Sunny Songs Record Cover
Michele's Collectibles (& Some Other Stuff) 
have a muller print, reframed of gnome conducting choir of squirrels, porcupine, crickets, birds, snail. frog, bear and rabbit. I have no idea of title.
Sounds like a brilliant print! I don’t think I have seen that one before. Is it a larger print? Most of mine are 5×5 or 8×8. But I have seen larger ones. I get most of the titles from being printed on the back or the postcards that were also produced. I would love to see a picture of the print!