Cover to Holland with French meter from Paris' Rue Bleue post office. The Republican government decided to mail the correspondence of the brigadists from countries considered hostile through the French post, from October 1937 to June 1938. As these covers do not bear any International Brigades marks, they can be easily confused with regular, abundant and worthless French meters of the 30's.
BUT... HERE IS THE JUSTIFICATION:
Cover from the same sender to the same addressee, with same calligraphy and Barcelona meter plus International Brigades censor mark on the back. So this one proves that the other before was genuniely sent by a Brigadist through the French mail.
Cover sent from the French camp for Spanish refugees of Gurs to Prague. The destination and the sender's info on the back could make you suspect this could be sent by a former brigadist.
AND YES! HE WAS A BRIGADIST! SEE THE CONFIRMATION:
Cover to the same addressee than the one sent from the Gurs camp, written by the same hand, and with International Brigades censor and postmarks, that proves that this brigadist later ended up in the French camps for refugees.
All these pieces are very rare, and in pairs are exceptionally rare. They are some gems of the Spanish Civil War postal history.