Bois, Marcel (30 April 2020). "'March Separately, But Strike Together!' The Communist Party's United-Front Policy in the Weimar Republic". Historical Materialism. 28 (3). Brill: 138–165. doi:10.1163/1569206x-00001281. ISSN1465-4466. S2CID219055035.
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Bois, Marcel (30 April 2020). "'March Separately, But Strike Together!' The Communist Party's United-Front Policy in the Weimar Republic". Historical Materialism. 28 (3). Brill: 138–165. doi:10.1163/1569206x-00001281. ISSN1465-4466. S2CID219055035.
Bois, Marcel (30 April 2020). "'March Separately, But Strike Together!' The Communist Party's United-Front Policy in the Weimar Republic". Historical Materialism. 28 (3). Brill: 138–165. doi:10.1163/1569206x-00001281. ISSN1465-4466. S2CID219055035.