Robertson, R. (2001). Karl Beck: From Radicalism to Monarchism. Year Book / Leo Baeck Institute.
Chicago-viite (17. p.)Robertson, Ritchie. "Karl Beck: From Radicalism to Monarchism." Year Book / Leo Baeck Institute 2001.
MLA-viite (8. p.)Robertson, Ritchie. "Karl Beck: From Radicalism to Monarchism." Year Book / Leo Baeck Institute, 2001.
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