Letter from Charles H. Miller to John Welsh relative to the purchase of a number of plants now on exhibition in the Horticultural Department - Centennial Grounds, 1876 October 11, Drawer: 5-4. History Files, FP.2010.001.006. Fairmount Park Historic Resources Archive. https://pprarchives.libraryhost.com/repositories/2/archival_objects/405699 Accessed April 20, 2025.