Não informado. (1940). Labor market and employment security. Bureau of Employment Security.
Citação do estilo Chicago (17ª ed.)Não informado. Labor Market and Employment Security. Washington: Bureau of Employment Security, 1940.
Citação MLA (8ª ed.)Não informado. Labor Market and Employment Security. Bureau of Employment Security, 1940.
警告：這些引文格式不一定是100％准確.