Marijac, Jacques Ernest Dumas

Hoping that someone can help me here. My grandfather monsieur Jacques Ernest Dumas was born in Paris in 1908 and as far as I know or should I say all that I know about his military/resistant history is that because he refused to go to German to do forced labor as he was ex-military he was shoved into a concentration camp due to him being concidered as a political prisoner rather then a POW. During his time in there he managed to escape from the concentration camp and joined the resistant movement. I know that he worked in publishing for newspapers such as La Liberation amongst others and later became famous as a cartoonist for his comic strips such as Les Trois Mousquetaires Du Maquis etc. Other then this, I know very little about his involvement during the war. I have tried to ask my mother and aunt but they were never interrested in his wartime history. My grandmother, god bless her, died not long after him (he died in 1994) and they are both buried in Lyons La Forêt. Is there anyone that can help me n finding out about his past. Bellow are liinks to images of his work.