This is precisely what I wonder about, dear Polignac ?
I have read that the court avoided "Yolande" because it sounded to medieval. The duchess was usely called "Jules" from her husband's name. She was the countess, and later, the duchess Jules.
On the net, you can find Y M G de Polastron or G M Y de Polastron, depending... Most of the historians call her Yolande, some others Gabrielle. Nobody Martine... They have our nowaday habit to use the firstname. However, it's wrong. XVIIIth people often used their second name, or even third.
To make it shorter, I guess she could be Gabrielle... or even Martine !
But all we can do know is ask the "oui-ja" and hope we won't fall upon Pazuzu !
