Concerning the links, I’m still wondering what are the relationships:
From the table isrc I get to recording then to artist and then I should have a table that links the artist with instruments but l_artist_instrument is an empty table.
The mapping between ISRC and MBID is pretty straightforward:
And yes, I know and will keep in mind that multiple ISRC can be linked to one MBID, which is a kind of internal ISWC?