Otto Junghans, Paul Richard Junghans, Carl F Yunghans

This is the only photo I've seen of three of the four Junghans (Yunghans) brothers together.

From left to right:   Otto Junghans,  my great grandfather, Paul Richard Junghans and Carl F Yunghans.

Eldest brother Emil Yunghans (who was not included in the photo) died February 19, 1929 in Vincennes, Indiana and Otto Junghans died June 16, 1931 in Mequon, Wisconsin.

I'm not sure where the photo (Vincennes, Indiana or in Wisconsin) was taken but based upon the deaths of Emil and Otto I am guessing the photo was taken sometime between February 1929 and June 1931.