Peden, W. C. (2013). From authority religion to spirit religion: An intellectual biography of George Burman Foster, 1857-1918. Cambridge Scholars Publishing.
Lua i Stíl Chicago (17ú heag.)Peden, W. Creighton. From Authority Religion to Spirit Religion: An Intellectual Biography of George Burman Foster, 1857-1918. Newcastle upon Tyne, England: Cambridge Scholars Publishing, 2013.
Lua MLA (9ú heag.)Peden, W. Creighton. From Authority Religion to Spirit Religion: An Intellectual Biography of George Burman Foster, 1857-1918. Cambridge Scholars Publishing, 2013.
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