Hello to all!

I've recently got my hands on two rolls of 620 format old film from the French producer. The ASA is 200, but the expiry date is March 66'.
I tried to search a bit but I haven't heard too much of this film (Only read about and used Guilleminot paper). Th format doesn't concern me too much, since I can alway roll it on a 120 spool (I believe, correct me if I'm wrong), but does anybody have any info or idea how should I develop/ expose the negative? I don't want to experiment a lot since I have only two rolls.

Thanks a lot,