REFERENCES
- Karl Baedeker, Central Italy and Rome, 15th rev. ed., Leipzig, 1909.
- Karl Baedeker, Italy, Handbook for Travellers, First Part: Northern Italy, 10th remodelled ed., Leipsic, 1895.
- Karl Baedeker, The Mediterranean, Leipzig, 1911.
- Karl Baedeker, Switzerland, 24th ed., Leipzig, 1911.
- Baedeker's Switzerland, Prentice Hall, Englewood Cliffs, no date.
- Eugenio Battisti, Filippo Brunelleschi: The Complete Work, Rizzoli, New York, 1981.
- Maurizio Calvesi, Treasures of the Vatican, Editions d'Art Albert Skira, 1962.
- Rev. William Augustus Brevoort Coolidge, “Lucerne”, in the Encyclopaedia Britannica, 11th ed., New York, 1910–1911, vol. XXVII, p. 97.
- Sir David Floyd Ewin, St. Paul's Cathedral, Pitkin Pictorials Ltd., London, 1975.
- Amato Pietro Frutaz, Il Complesso Monumentale di Sant'Agnese, 2nd ed., Tipografia Poliglotta Vaticana, Roma, 1969.
- Rolando and Pietro Fusi, Florence, Bonechi—Edizioni “Il Turismo,” Firenze, late 1970s.
- A Glossary of Terms Used in Grecian, Roman, Italian, and Gothic Architecture, 4th rev. ed., Oxford, John Henry Parker, 1845.
- Emanuele Romanelli, Santa Maria in Aracoeli, Tipografia V. Lozzi, Via Tommaso Silvestri 11, Roma, no date.
- R. Phené Spiers, “Vault,” in the Encyclopaedia Britannica, 11th ed., New York, 1910–1911, vol. XXVII, pp. 956–961.