Thank you Verktyg for your great knowledge !
I think also it is probably not a super chalenge , because it has the number under the BB identical with two other lugless frame PEUGEOT of my collection...
number of this GITANE: Y80701627
number of my 1986 PEUGEOT P10SA : Y60953539
number of my 1991 PEUGEOT "Tourmalet" :Y10808957
So, it is certainly a lugless frame built in the PEUGEOT factory of Romilly-sur-Seine and not in the historical GITANE factory of Machecoul...
I think it is probably a 1998 model,perhaps "mach 300" built by the new group formed by PEUGEOT, GITANE, BH, called CYCLEUROP , in Romilly factory where PEUGEOT invented and perfected the technique of lugless brazing.
And I can say that this GITANE frame is absolutely identical with my PEUGEOT P10SA (picture)...
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