Ledo, R. (1961). Language testing: The construction and use of foreign language tests. Longmans.
Chicago-viite (17. p.)Ledo, Robert. Language Testing: The Construction and Use of Foreign Language Tests. [London]: Longmans, 1961.
MLA-viite (9. p.)Ledo, Robert. Language Testing: The Construction and Use of Foreign Language Tests. Longmans, 1961.
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