Author
American Jewish Historical Society
7
Harry Houdini Collection (Library of Congress)
7
Swiss-American Historical Society
7
American Historical Association
6
American Jewish Congress
6
Archives of American Art
6
Lusaka Mission Service
6
Reformed Church in the United States
6
Union of American Hebrew Congregations
6
United States. Continental Congress
6
American Gymnastic Union
5
American-Scandinavian Foundation
5
Armenian Assembly of America
5
Armenian General Benevolent Union
5
B'nai B'rith. Anti-defamation League
5
Balzekas Museum of Lithuanian Culture
5
Center for Migration Studies (U.S.)
5
Collom, William
5
Hagley Museum and Library
5
Order of Ahepa
5
Organization of American Historians
5
Polish Institute of Arts and Sciences in America
5
Ukrainian Congress Committee of America
5
University of Pennsylvania. Botanical Laboratory
5
Zionist Organization of America
5
American Association for Jewish Education
4
American Latvian Association in the United States
4
American Protestants for Truth about Ireland
4
American-Irish Historical Society
4
Association for the Advancement of Baltic Studies
4
Egelmann, Charles Frederick
4
Federation of Jewish Agencies of Greater Philadelphia
4
Henry Francis du Pont Winterthur Museum
4
Intergovernmental Committee for European Migration
4
Mississippi Valley Historical Association
4
National Federation of Temple Brotherhoods
4
North American Gymnastic Union. Normal College
4
Norwegian-American Historical Association
4
Philadelphia (Pa.). Department of Records
4
Polish American Council
4
Polish American Historical Association
4
Polish Genealogical Society of America
4
Polish National Alliance of the United States of North America
4
Polonus Philatelic Society
4
R.L. Polk & Co
4
Research Group for European Migration Problems
4
Slovak League of America
4
Society for German-American Studies (U.S.)
4
Society of American Archivists
4
Swedish-American Historical Society
4
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