Polish Army in France WWI

[Regis Hoffman]

I have been researching some local history of my hometown of Pittsburgh (USA) and have discovered that it was a center of recruitment of Poles to return to Europe to fight in the Polish Army of France during WWI.

Does anyone have an example of mail from this force back to the US (implying the sender was recruited in the US)?

I understand these might be very scarce...

Thanks!