Calculating Map Overlay Polygon' Areas Without Explicitly Calculating the Polygons --- Implementation

@inproceedings{f-cmopa-90,
    author = "Franklin, Wm Randolph",
    title = "Calculating Map Overlay Polygon' Areas Without Explicitly Calculating the Polygons --- Implementation",
    booktitle = "4th International Symposium on Spatial Data Handling",
    month = "23-27 July",
    year = "1990",
    pages = "151--160",
    address = "Zürich",
    href = "\bibhref{67-sdh90-overlay}",
    precedes = "fsskn-ofmop-93",
    mykey = "overlay",
    keywords = "intersection, area, grids, measure, polygons"
}