----------------------------Original message---------------------------- At CSU-Long Beach, we have our 1990 Census of Population and Housing Tract and Block maps in open government document stacks, arranged by sudoc. They are folded in their original white and green envelopes. I am looking for ways to make at least the Los Angeles and Long Beach maps more durable. I am considering "Chartexing" them, folding them accordion-style to 1/3 their original size, and binding every 5 sheets with three or four key-ring holders at the edge. By using this method, the maps would still be flexible and maneuverable for photocopying. Does anyone have any other ideas? I do not have the option of enclosing them behind a service point or into the map collection. Any other conservation methods employed out there? Thanks. Greg Armento California State University, Long Beach