Harnack, A. (1957). What is Christianity? Harper & Brothers.
Chicagoスタイル(17版)引用形式Harnack, Adolf. What Is Christianity? New York: Harper & Brothers, 1957.
MLA(9版)引用形式Harnack, Adolf. What Is Christianity? Harper & Brothers, 1957.
警告: この引用は必ずしも正確ではありません.