Não informado. (1940). Labor market and employment security. Bureau of Employment Security.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Labor Market and Employment Security. Washington: Bureau of Employment Security, 1940.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Labor Market and Employment Security. Bureau of Employment Security, 1940.
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