Easton, P. A. (1996). Sharpening our tools: Improving evaluation in adult and nonformal education. UNESCO Institute for Education.
Chicago-viite (17. p.)Easton, Peter A. Sharpening Our Tools: Improving Evaluation in Adult and Nonformal Education. Hamburg, Germany: UNESCO Institute for Education, 1996.
MLA-viite (8. p.)Easton, Peter A. Sharpening Our Tools: Improving Evaluation in Adult and Nonformal Education. UNESCO Institute for Education, 1996.
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