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

• 5-speed 1939
• Lightweight 5-speed 1939
• 1950
• Lightweight alloy

I think that more correct labels might be:

• Le Cyclo 5-speed 1939
• Le Cyclo 5-speed 1939
• Cyclo Route 1950
• Le Cyclo Leger

• Publisher: New Cycling
• Document: New Cycling May 1981 - '81 Derailleur Collection
• Date: May 1981
• Derailleur brands: Cyclo
• Derailleurs: Le Cyclo 5-speed 1939, Le Cyclo Leger, Cyclo Route 1950