France/US child custody

My ex husband took my daughter on a vacation to france with a paper from me who gave him permission to take her since i have full custody. On his trip there he called me and told me he planned to stay there all along. I went there and found i couldn't do anything to take her back without his consent. I don't know what i need to do to get her back. I read about the Hague Convention but i want more information. I am devastated. My little girl was born in france, but is also a US citizen so am I.

[AFFA]

I wish to inform you that the United States and France signed the Hague Convention in 1988. This was done after the US approved the International Child Abduction Remedies Act. You may approach the Bureau de l'entraide judiciaire en matière civile et commerciale (Ministry of Justice) in France. Your application may be in French or should have a French translation. The Ministry will forward your file to the Public Prosecutor of the area where your ex husband resides. You may also approach the International Mediation Mission for Families in the Ministry of Justice. Alternatively, you can contact the tribunal de grande.

AFF