A bergerette, or shepherdess' air, is a form of early rustic French song.
Here is a known melody easy piano duet 4-hands composed in 18th century by the French composer Pierre-Alexandre Monsigny (1729-1817). 
Pages: 3 pages both hands, 1 page prima, 1 page seconda, 1:22 min, with downloadable mp3 for audio help.

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.

A romantic minuet sonatine for Cello and Piano. Contains the cello and piano score and the cello part.
By Philipe Lamaury (1837-1890)
With downloadable mp3 for audio help.
Pages: 4 pages, 3' min, 78 bars.

April in Paris is a popular song composed by Vernon Duke with lyrics by Yip Harburg in 1932 for the Broadway musical Walk a Little Faster. Frenh lyrics by Emelia Renaud. It has been performed by many artists, including Louis Armstrong, Count Basie, Billy Eckstine, Bill Evans, Charlie Parker, Coleman Hawkins, Frank Sinatra.

Here is an arrangement for Violin (plays the melody) and Piano duet. 
With lyrics (english and french), guitar chords and melody line. 
Violin : early intermediate. Piano Advanced Intermediate.
Seven pages (5 pages both violin and piano, 2 pages violin), 4' min.

Ave Maria for FLUTE and Piano Duet.
9 pages (7 pages both piano and flute, 2 pages flute part).
5:50 min, widh downloadable mp3 for audio help.