Coburn, Frederick W. Rapid Transit and Civic Beauty. New Boston. Vol. 1 no. 7. November 1910: 307–314 [2020-08-21]. (原始内容存档于2020-06-09) –通过Google Books.
Coburn, Frederick W. Rapid Transit and Civic Beauty. New Boston. Vol. 1 no. 7. November 1910: 307–314 [2020-08-21]. (原始内容存档于2020-06-09) –通过Google Books.