Tolong jelaskan mengenai Lihat pula dari Biennio Rosso

Neufeld, Maurice F. (1961). Italy: school for awakening countries - The Italian labor movement in its political, social, and economic setting from 1800 to 1960, New York State School of Industrial and Labor Relations, Cornell University.

Pelz, William A. (2007). Against Capitalism: The European Left on the March, New York: Peter Lang,