Philip Schaff

• History of the Christian Church, vol. 1, 3rd rev. (1910) [link]; vol. 2, 9th ed. (1910) [link]; vol. 3, 6th ed. (1908) [link]; vol. 4 (1918) [link]; vol. 5.1 (1907) [link]; NOTE also html version of the 1910 edition at CCEL
• The Creeds of Christendom, 4th ed., vol. 3 (1919) [link]; cf. also html version of the 6th / 1919 ed. at CCEL
• The New Schaff-Herzog Encyclopedia of Religious Knowledge
• vol. 1 [Aachen - Basilians] (1908) [link]
• vol. 2 [Basilica - Chambers] (1908) [link]
• vol. 3 [Chamier - Draendorf] (1909) [link]
• vol. 4 [Draeseke - Goa] (1909) [link]
• vol. 5 [Goar - Innocent] (1909) [link]
• vol. 6 [Innocents - Liudger] (1910) [link]
• vol. 7 [Liutprand - Moralities] [link]
• vol. 8 [Morality - Petersen] (1910) [link]
• vol. 9 [Petri - Reuchlin] (1911) [link]
• vol. 10 [Reuch - Son of God] (1911) [link]
• vol. 11 [Son of Man - Tremellius] (1911) [link]
• vol. 12 [Trench - Zwingli; appendix] (1912) [link]