Wal, D. v. d., & Snouck Hargronje, C. (2011). Christiaan Snouck Hurgronje: The first western photographer in Mecca, 1884-1885.
Lua i Stíl Chicago (17ú heag.)Wal, Durkje van der, agus Christiaan Snouck Hargronje. Christiaan Snouck Hurgronje: The First Western Photographer in Mecca, 1884-1885. Amsterdam, 2011.
Lua MLA (8ú heag.)Wal, Durkje van der, agus Christiaan Snouck Hargronje. Christiaan Snouck Hurgronje: The First Western Photographer in Mecca, 1884-1885. 2011.
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