My source of archival materials: http://www.conservationresources.com/
My method is the 4-fold envelopes, http://www.conservationresources.com...ection5_05.htm -- data written on the envelopes.
Stored in boxes, http://www.conservationresources.com...ection5_12.htm
But as mentioned before, the most important part is the organization and record-keeping. Otherwise, the collection is not a true collection and more likely to be tossed someday.
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