Não informado. (1989). Educational Technology Research and Development. Association for Educational Communications and Technology.
শিকাগো স্টাইল (17 তম সংস্করণ) উদ্ধৃতিNão informado. Educational Technology Research and Development. Washington: Association for Educational Communications and Technology, 1989.
M.L.A (8 ম সংস্করণ) উদ্ধৃতিNão informado. Educational Technology Research and Development. Association for Educational Communications and Technology, 1989.
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