Part of the Frick Collection Archives Repository
Knickerbocker Slate Corp.. The Frick Collection Construction Records, TFC.0500.010. Frick Collection Archives.
Knickerbocker Slate Corp.. The Frick Collection Construction Records, TFC.0500.010. Frick Collection Archives. https://archives.frick.org/repositories/3/archival_objects/21334 Accessed June 08, 2025.
