Hoffmann, M., K. Kaufmann-Kuchta, T. Kutscher, J. Merkel, S. Widany, M. Wiest, and J. Willeke. “The Potential of Statistical Matching for the Analysis of Wider Benefits of Learning in Later Life”. European Journal for Research on the Education and Learning of Adults, vol. 10, no. 3, Oct. 2019, pp. 291-06, doi:10.3384/rela.2000-7426.rela201910.