Ocarina and recorder, A2 and A4: Pierre Poulteau
Piano B1 and B2: Raoul Galo
Double bass B5: Georges Melot
Possible variations over the course of the pressings: different round record labels (red or white-blue-red), various sleeve printing types (for example ‘glossy’ appearance or not), different sleeve printing companies, different contact details for the Music De Wolfe office in London, pressing of the records in England or Holland.
Maybe also published on audio cassette.