My random translations of the photo captions, clockwise from top left are:

• Allvit Super III
• Svelto
• Luxe
• Svelto

It's nerdy, but I think that the correct labels might be:

• Huret Super Allvit III
• Huret Svelto
• Huret Luxe Compétition
• Huret Svelto

• Publisher: New Cycling
• Document: New Cycling May 1981 - Derailleur Collection
• Date: May 1981
• Derailleur brands: Huret
• Derailleurs: Huret Luxe Compétition, Huret Super Allvit III, Huret Svelto (1st style), Huret Svelto