Organisation for Economic Co-operation and Development. (2017). The nature of problem solving: Using research to inspire 21st century learning. OECD.
Chicago-čujuhus (17. p.)Organisation for Economic Co-operation and Development. The Nature of Problem Solving: Using Research to Inspire 21st Century Learning. Paris: OECD, 2017.
MLA-čujuhus (9. p.)Organisation for Economic Co-operation and Development. The Nature of Problem Solving: Using Research to Inspire 21st Century Learning. OECD, 2017.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.