found: Fremlin, G. Maps as mediated seeing, c1999:abstr. ("Thematic maps, using imagery based on visual metaphors, depict localized processes of the universe rather than the objects that are represented on topographical maps.") p. 129 (Map, Thematic: a map which has signage added either to a topographical base-map or else to a geodetic graticule only, that depicts a subject, e.g. geology, population, air temperature, etc. that can be interpreted as a sub-process of the universe. Process, as the general subject of all thematic maps distinguishes them from topographical maps whose general subject is perceived objects in perceived three-dimensional space. According to Robinson and Petchenik (1976) the term "thematic map" was invented (in German) by N. Creutzberg in 1953.")
found: Dent, B.D. Cartography : thematic map design, c1996:p. 5 ("In general, all maps may be classified as either general-purpose or thematic types.") p. 6 (thematic map, also called a special-purpose, single-topic, or statistical map; "The International Cartographic Association defines thematic map this way: 'A map designed to demonstrate particular features or concepts. In conventional use this term excludes topographic maps.'")
found: Elements of cartography, c1995:pp. 12-13 (three main classes of maps: general reference maps, thematic maps, and charts; "... thematic or special purpose maps ... concentrates on the distribution of a single attribute or the relationship among several.")
found: Fisher, H.T. Mapping information, c1982:p. 6 ("General reference maps place little emphasis on obviously quantitative differences (with the exception of terrain height). In contrast, thematic maps emphasize quantitative differences through extensive use of graphic symbolism. General reference maps primarily depict physical characteristics on or near the surface of the earth and major political boundaries. Thematic maps may deal with any conceivable subject in any location, including nonphysical events and totally abstract or hypothetical matters. Individual thematic maps usually portray only one or a few subjects that are similar or clearly related. In contrast, many general reference maps treat a considerable number of subjects that are often unrelated except for sharing a common study space.")
found: Clark, A.N. The new Penguin dict. of geography, 1990(thematic map: a map on any scale representing a specific spatial distribution, theme, topic or aspect under discussion)
found: Cuff, D.J. Thematic maps, 1982.
