Charles Angelich wrote in a message to Roy J. Tellason:

CA> Sunlight and heat are catalysts. They damage paper rapidly.  

I don't know about those,  but the problems I've had have mostly been
caused by moisture.  I can still remember one particular storage unit that
I'd rented,  where I put some boxes of my books into it.  They hadn't
closed up the back of it properly,  from the top of the block wall to the
roof,  and I knew I had a problem when I went over there once during winter
weather and opened the door to find the floor covered in a sheet of ice... 
Lost a *bunch* of stuff that way.

Nowadays I'll keep books I don't have room to shelve around the apartment
in boxes in the apartment,  rather than in storage with the rest of my
junk.

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