"Action plan."; "America's Industrial and Heritage Project."; "America's Industrial Heritage Project."; "Industrial sites--Pennsylvania.", "Historic sites--Conservation and restoration--Pennsylvania."; "America's Industrial and Heritage Project."; "1987"; "

Monograph.

"; ""; "P20198"; "pec"; "America's Industrial Heritage Project.", "Historic sites--Conservation and restoration--Pennsylvania.", "Industrial sites--Pennsylvania."; "14256"; .