@book{Harnack, author = {Harnack, D. A. von}, title = {Dogmengeschichte (= Grundriß der Theologischen Wissenschaft, 4th part, vol. III), 6th and revised editlion, T{\"u}bingen (Verlag J. C. B. Mohr (Paul Siebeck)) 1922.}, language = {de} } @book{Harnack, author = {Harnack, D. A. von}, title = {What is Christianity? New York (Harper \& Brothers) 1957.}, language = {en} }