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The American Institute of Architects Archives
Membership file contains membership application, correspondence about dues, reapplication, transfers to newly formed chapters, notification of death, obituaries. The exhibits submitted with his application were returned to him at the time.
University of North Texas Special Collections
David S. Castle Architectural Drawings Collection, 1914-1962
Finding aid to the collection is available at https://findingaids.library.unt.edu/?p=collections/findingaid&id=877. Digitized drawings are available through the Portal to Texas History https://texashistory.unt.edu/explore/collections/DVDCAD/
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