APA
Piggott J., Whalley J., . (1998). Vat base broadening, self supply, and the informal sector. Cambridge, Mass: National Bureau of Economic Research.
Chicago
Piggott John, Whalley John, . 1998. Vat base broadening, self supply, and the informal sector. Cambridge, Mass: National Bureau of Economic Research.
Harvard
Piggott J., Whalley J., . (1998). Vat base broadening, self supply, and the informal sector. Cambridge, Mass: National Bureau of Economic Research.
MLA
Piggott John, Whalley John, . Vat base broadening, self supply, and the informal sector. Cambridge, Mass: National Bureau of Economic Research. 1998.