(1931). The international regulation of hours of work in coal mines. International Labour Organization.
Citazione stile Chigago Style (17a edizione)The International Regulation of Hours of Work in Coal Mines. International Labour Organization, 1931.
Citatione MLA (9a ed.)The International Regulation of Hours of Work in Coal Mines. International Labour Organization, 1931.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.