Composed by Joseph Bonnet, Twelve pieces, Op.7 is a set of Organ studies for upper intermediate players. An index at the beginning gives an English translation of the terms used in the book.

It features:
1. Dédicace
2. Étude de concert
3. Clair de lune
4. Stella matutina
5. Songe denfant
6. Chant de Printemps
7. Prélude au Salve Regina
8. Romance sans Paroles
9. Pastorale
10. Deuxième légende
11. Elfes
12. Caprice héroïque

Joseph Jongen was a Belgian organist, composer and professor of harmony and counterpoint. He won the Belgian Prix de Rome and composed numerous pieces including music chamber works, symphonies, concertos and songs. His most famous piece is the Symphonie Concertante (1926).