Gras, N. S. B. (1967). The evolution of the English corn market, from the twelfth to the eighteenth century. Russell & Russell.
Chicago-viite (17. p.)Gras, Norman Scott Brien. The Evolution of the English Corn Market, from the Twelfth to the Eighteenth Century. New York: Russell & Russell, 1967.
MLA-viite (8. p.)Gras, Norman Scott Brien. The Evolution of the English Corn Market, from the Twelfth to the Eighteenth Century. Russell & Russell, 1967.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.