Unesco. Progress of literacy in various countries: A preliminary statistical study of available census data since 1900. Unesco.
Chicago-viite (17. p.)Unesco. Progress of Literacy in Various Countries: A Preliminary Statistical Study of Available Census Data Since 1900. Unesco.
MLA-viite (8. p.)Unesco. Progress of Literacy in Various Countries: A Preliminary Statistical Study of Available Census Data Since 1900. Unesco.
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