@article {Walton:1989-06-01T00:00:00:0008-7041:33,
	author = "Walton, D. J.",
	title = "A Computer Aided Geometric Design approach to contour map editing",
	journal = "Cartographic Journal, The",
	volume = "26",
	number = "1",
	year = "1989-06-01T00:00:00",
	abstract = "A contour map is a convenient representation of three-dimensional data. Although, when displayed, it does not provide an immediate visual three-dimensional image, it is useful in practical applications. It is tedious to manually draw or extract data from a contour map. The ability to store contour maps for computer processing is thus desirable. A contour map is conventionally stored in a computer as a set of polygons. This method unfortunately requires a large amount of storage and is not convenient for subsequent editing of contour maps. More recent techniques use cubic splines with mathematical continuity. Although such techniques require less storage than the conventional method, they do not provide a convenient means for subsequent editing. From recent reports on research in Computer Aided Geometric Design as well as in Computer Aided Design and Computer Aided Manufacturing, it seems that cubic splines with geometric continuity rather than mathematical continuity are more appropriate for computer graphics applications. This article examines the appropriateness of geometric continuity in the development of software for contour map editing.",
	pages = "33-38",
	url = "http://www.ingentaconnect.com/content/maney/caj/1989/00000026/00000001/art00007",
	doi = "doi:10.1179/000870489787321015"
}