National Planning Institute. (2007). The virtual water concept. National Planning Institute.
Chicagoスタイル(17版)引用形式National Planning Institute. The Virtual Water Concept. cairo.: National Planning Institute, 2007.
MLA(9版)引用形式National Planning Institute. The Virtual Water Concept. National Planning Institute, 2007.
警告: この引用は必ずしも正確ではありません.