Here are some good books, but they are more about
art than framing, per se.
Hugh
CLAPP, ANNE F. Curatorial Care of Work of Art on Paper. Oberlin, Ohio: Intermuseum Laboratory, 2d rev. ed., 1974.
DOLLOFT, FRANCIS W., and PERKINSON, Roy L. How to Care for Works of Art on Paper. Boston: Museum of Fine Arts, 1971.
ELLIS, MARGARET HOLBEIN, The Care of Prints and Drawings. AltaMira P 1995.
GLASER, MARY TODD. "Framing & Preservation of Works of Art on Paper." New York: Parke Bernet Galleries, 1971.
JAMES, CARLO et al., Old Master Prints and Drawings: A Guide to Preservation and Conservation. Amsterdam: Amsterdam Univ. Press 1997.
KING, ANTOINETTE. "Care and Conservation of Prints" in Castleman, Riva. Modern Art in Prints. New York: Museum of Modern Art, 1973.
ZIGROSSER, CARL, and GAEDHE, CHRISTA M. A Guide to the Collecting and Care of Original Prints. New York: Crown Publishers, 1965.