Grotlüschen, A.; Mallows, D.; Reder, S.; Sabatini, J. (2016), “Adults with Low Proficiency in Literacy or Numeracy”, OECD Education Working Papers, No. 131, OECD Publishing, Paris. hier
Grotlüschen, A.; Mallows, D.; Reder, S.; Sabatini, J. (2016), “Adults with Low Proficiency in Literacy or Numeracy”, OECD Education Working Papers, No. 131, OECD Publishing, Paris. hier