van der Walt, J. L., and C. C. Wolhuter. “An Examination of the Potential of Culturalhistorical Activity Theory (CHAT) for Explaining Transitions in National Education Systems”. Acta Academica: Critical Views on Society, Culture and Politics, vol. 50, no. 1, Aug. 2018, pp. 104-25, doi:10.18820/24150479/aa50i1.6.