France is known to be quite active on the market of first day covers.

A total of 5 different cachet covers have been identified up to now. All of them are cancelled in Paris on 12 April 1958. Cancellations in other countries are not known.

Set stamp covers:

Besides the FDCs above, you have also the below special card with some explanations of the Exhibition:

For the sake for the person who has done the effort of creating an own FDC with original cancellation, I have added the following as well: