The Clan Keith Society USA, Inc. – The only society recognized by the Chief of Clan Keith, the Earl of Kintore, as representing the Clan Keith in the United States of America.
Horsham Preservation and Historical Association
Pennsylvania Historical and Museum Commission
PHMC Collection at the PA State Museum
Trailheads Blog – news of the sites along the Pennsylvania Trails of History
ushistory.org– The website of historic Philadelphia and region.