I recently learned a paper-smoothing technique that works very well and is
generally safe-- wet the paper on the back only, with a brush or mister.
Allow it to saturate until the paper flattens; you may need to re-spray
once or twice. When the paper is completely flat, let it sit until the
corners start to curl up. Then lay it on a flat surface, on top of a clean
towel; place another towel on top of it, then a heavy board (which you can
further weight with books etc.). Leave it there for about 24 hours; change
the towels once. This method preserves the margins and doesn't wet the
front. Still, I'd do an experimental scrap first, as the paper is
unfamiliar and you never know.
Marlene Hill Donnelly
Field Museum, Dept. of Geology
Roosevelt Rd at Lake Shore Drive
Chicago, IL 60605