https://imslp.org/wiki/Category:Scores_featuring_the_piano_4_hands_(arr)
Category:Scores featuring the piano 4 hands (arr) - IMSLP
piano 4 handscategoryscoresfeaturingarr
https://www.musiciansfriend.com/books-sheet-music-media/schott-mohrentanz-und-mummenschanz-1-piano-4-hands-schott-series/k19851000000000
Schott Mohrentanz und Mummenschanz (1 Piano, 4 Hands) Schott Series | Musician's Friend
piano 4 hands
https://www.musiciansfriend.com/books-sheet-music-media/schott-original-piano-duets--volume-2-piano-4-hands-schott-series/k08012000000000
Schott Original Piano Duets - Volume 2 (Piano, 4 Hands) Schott Series | Musician's Friend
piano duetsvolume 2