The International Communist Current, itself a Left Communist grouping, has produced a series of studies of what it views as its own antecedents. The book on the German-Dutch current, which is by Philippe Bourrinet (who later left the ICC), in particular contains an exhaustive bibliography.
Also of interest is volume 5 number 4 of Spring 1995 of the journal Revolutionary History : "Through Fascism, War and Revolution: Trotskyism and Left Communism in Italy".
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