Greater London Council Public Information Branch. "Jubilee Line: Preparatory Drilling Begins." Public Information Branch News Service. No. 217. London: Greater London Council, 1977., June 30, 1977

Greater London Council Public Information Branch. "Jubilee Line: Preparatory Drilling Begins." Public Information Branch News Service. No. 217. London: Greater London Council, 1977., June 30, 1977, Box: 1, Folder: 20. Robert Kraushaar papers, 6754. Division of Rare and Manuscript Collections. https://aspace3-test.library.cornell.edu/repositories/2/archival_objects/542428 Accessed May 10, 2025.