One-half or more of the developing world's nonagricultural workers are employed in the underground informal sector, according to the International Labour Organization.
Arrighi, G. "Labour Supplies in Historical Perspective: A Study of the Proletarianization of the African Peasantry in Rhodesia." Journal of Development Studies 6 (1970).
But those who favor the influx of the cheap labor force , on the other side, maintain that migrants are needed for the massive urban infrastucture contruction program.