God Save The Queen, for piano duet 4 hands.
Pages: 4 pages (2 pages both hands, 1 page prima, 1 page seconda), with downloadable mp3s for audio help.

12 short duets for 1 piano 4 hands.
Includes Reverie, A little waltz, Merry go round, March, Rememberance, Waltz, Quite contented, Bag-pipes, Bolero, The Brook, Lullaby, Good-by.
Easy piano,15 pages.
With downloadable mp3s for audio help.

Three preludes for piano duet 4 hands, by R.Hahn.
Includes :
The Little Red Lark, My Love's An Arbutus, The Willou Tree.
Contains separate sheet music parts for each player, and sheet music with both parts together.
With  downloadable mp3s for each player and both, and midi files for practice, 31 pages.

Piano duet is Fun a bright cheerful, rythmical and fun duet for piano duet (1 piano 4-hands).
By Juan Morel Campos (1857-1896).
Transcribed for early-intermediate to intermediate level.
Includes downloadable mp3 with both parts and separate parts with count-in measures for play-along learning purposes, 2:20' min, 13 pages (primo 3 pages, secondo 3 pages, both 6 pages, cover 1 page).

Ave Maria by Charles Francois Gounod, arranged for 4 hands intermediate piano 4 pages (prima 2 pages, seconda 2 pages) 2' min,
With downloadable mp3 for audio help.
First publiushed 1876.