Removing mold from a railroad print

O Fenton Wells
 

This is kinda off topic but I have a railroad print that I forgot I had and after 6 or 7 moves I found it in a tube and it has some light brown mold on it.  Does anoyoone know how to remove the mold without hurting the print.
I hope the jail cell is warm and the food is good
Fenton Wells

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