(1949). Population census methods.
Chicago-viite (17. p.)Population Census Methods. Lake Success, N.Y, 1949.
MLA-viite (8. p.)Population Census Methods. 1949.
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(1949). Population census methods.
Chicago-viite (17. p.)Population Census Methods. Lake Success, N.Y, 1949.
MLA-viite (8. p.)Population Census Methods. 1949.