Ramm, B. (1953). Types of apologetic systems: An introductory study to the Christian philosophy of religion. Van Kampen.
Chicago-čujuhus (17. p.)Ramm, Bernard. Types of Apologetic Systems: An Introductory Study to the Christian Philosophy of Religion. Wheaton: Van Kampen, 1953.
MLA-čujuhus (9. p.)Ramm, Bernard. Types of Apologetic Systems: An Introductory Study to the Christian Philosophy of Religion. Van Kampen, 1953.
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