Author
Philadelphia Record
10
Conservation Center for Art and Historic Artifacts
9
National Trust for Historic Preservation in the United States
7
American Association for State and Local History
6
United States. National Park Service
6
O'Connell, Merrilyn Rogers
5
Rath, Frederick L.
5
Guldbeck, Per E.
4
Philadelphia Historical Commission
4
Cunha, George Daniel Martin
3
Fairmount Park Conservancy (Philadelphia, Pa.)
3
Historical Society of Pennsylvania
3
Keck, Caroline K.
3
Leeds, Joseph
3
Morrow, Carolyn Clark
3
National Conservation Advisory Council (U.S.)
3
Nature Conservancy (U.S.)
3
Pennsylvania Historical and Museum Commission
3
Philadelphia Historic Preservation Corporation
3
Philadelphia Museum of Art
3
Preservation Alliance for Greater Philadelphia
3
Research Libraries Group
3
Ritzenthaler, Mary Lynn
3
Tinkcom, Margaret B. 1907-
3
American Chemical Society. Cellulose, Paper, and Textile Division
2
Barrow, W. J. 1904-1967
2
Barrow, William J.
2
Batcheler, Penelope Hartshorne
2
Blades, William, 1824-1890
2
Bucks County Conservancy
2
Clapp, Anne F.
2
Cotton, Randy
2
Cunha, Dorothy Grant
2
Curtis Organ Restoration Society (Philadelphia, Pa.)
2
Darling, Henry R.
2
Davies, Thomas L.
2
Delaware Estuary Program
2
Delaware Historical Records Advisory Board
2
Delaware River Basin Commission
2
Delaware. Division of Historical and Cultural Affairs
2
Dickey, Weissman, Chandler, Holt (Firm)
2
Fall, Frieda Kay, 1913-
2
Historic American Buildings Survey
2
Kidney, Walter C.
2
Library of Congress
2
Moorland Studios Inc
2
New York State Historical Association
2
Northeast Document Conservation Center
2
Pennsylvania Environmental Council
2
Philadelphia (Pa.). Redevelopment Authority
2
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