APA
Estados Unidos, Estados Unidos & Sri Lanka. (1980). Agricultural commodities. [Washington: Government Printing Office.
Chicago
Estados Unidos, Estados Unidos and Sri Lanka. 1980. Agricultural commodities. [Washington: Government Printing Office.
Harvard
Estados Unidos, Estados Unidos and Sri Lanka. (1980). Agricultural commodities. [Washington: Government Printing Office.
MLA
Estados Unidos, Estados Unidos and Sri Lanka. Agricultural commodities. [Washington: Government Printing Office. 1980.
Folletos