Aunio, P., Mononen, R., Laine, A., van der Aalsvoort, G., Compagnie, C., Desoete, A., … de Wit, T. (2015). Mathematical learning difficulties – snapshots of current European research. LUMAT: International Journal on Math, Science and Technology Education, 3(5), 647–674. https://doi.org/10.31129/lumat.v3i5.1011