Sproul, R. C. (1997). Grace unknown: The heart of reformed theology. Baker.
Lua i Stíl Chicago (17ú heag.)Sproul, R. C. Grace Unknown: The Heart of Reformed Theology. Grand Rapids: Baker, 1997.
Lua MLA (9ú heag.)Sproul, R. C. Grace Unknown: The Heart of Reformed Theology. Baker, 1997.
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