APA (7th ed.) Citation

Luther, M. (1888). Quaestio circularis de signis gratiae. 1520.

Chicago Style (17th ed.) Citation

Luther, Martin. Quaestio Circularis De Signis Gratiae. 1520. 1888.

MLA (9th ed.) Citation

Luther, Martin. Quaestio Circularis De Signis Gratiae. 1520. 1888.

Warning: These citations may not always be 100% accurate.