1. These wage differences are usually linked to geographic labour demand and supply. 2. It argues that international migration starts from the labour demands of modern civilization. 3. A firm's labour demand is based on its marginal physical product of labour ( MPP L ). 4. They imported so many African slaves to fill the labour demands that the population became predominantly African in ethnicity. 5. Cotton required intensive labour over a long growing period, and this resulted increasing labour demands on the tenants. 6. Increased labour demand resulted in mass immigration, especially from British India and nationalist movements in the colonial territories. 7. Increased labour demand resulted in mass immigration, especially from British India and China, which brought about massive demographic change. 8. Thus, the purpose of the one-year qualifying period was to benefit the domestic economy by increasing labour demand. 9. At the time, southern Vietnam was beset by heavy corv�e labour demands, especially with large-scale roadworks in progress. 10. One such study, the 2007 TechTalentBC Labour Demand survey, was undertaken with the assistance of the Information and Communications Technology Council.