National Book Development Council of Singapore. (1981). First national readership survey. National Book Development Council of Singapore.
Chicago-viite (17. p.)National Book Development Council of Singapore. First National Readership Survey. [Singapore]: National Book Development Council of Singapore, 1981.
MLA-viite (8. p.)National Book Development Council of Singapore. First National Readership Survey. National Book Development Council of Singapore, 1981.
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