Hafkamp, W. A. (1984). Economic-environmental modeling in a national-regional system: An operational approach with multi-layer projection. North-Holland.
芝加哥风格引文Hafkamp, Wilhelms A. Economic-environmental Modeling in a National-regional System: An Operational Approach with Multi-layer Projection. New York: North-Holland, 1984.
MLA引文Hafkamp, Wilhelms A. Economic-environmental Modeling in a National-regional System: An Operational Approach with Multi-layer Projection. North-Holland, 1984.
警告：这些引文格式不一定是100％准确.