van Stekelenburg, J., N. C. Anikina, W. T. J. L. Pouw, I. Petrovic, and N. Nederlof. “From Correlation to Causation: The Cruciality of a Collectivity in the Context of Collective Action”. Journal of Social and Political Psychology, Vol. 1, no. 1, Dec. 2013, pp. 161-87, doi:10.5964/jspp.v1i1.38.