Unknown tuplet format
I recently downloaded 'Rhapsody in Blue 1924' both to enjoy the playback and explore the rather exotic notation. For the most part I understood the notation and how one could use MuseScore to enter it except when it came to measures 34 and 35. I have no idea how to build the tuplets in those measures or what the slashes across the stems mean and would appreciate an explanation on how to build them. Measure 34 is attached.