Mark, D.M. & Frank, A.U. 1989. Concepts of Space and 
Spatial Language. AUTO CARTO 9. Ninth 
International Symposium on Computer-Assisted 
Cartography. Baltimore, Maryland, pp. 538-556. 
Molenaar, M. 1991. Formal Data Structures, Object 
Dynamics and Consistency Rules. In: Ebner, H., Fritz, 
D. & Heipke, C. (Eds). Digital Photogrammetric 
Systems. Wichmann, Karlsruhe, pp. 262-273. 
NCDCDS, 1987. Issues in Digital Cartographic Data 
Standards. Report #8, A Draft Proposed Standard for 
Digital Cartographic Data. National Committee for 
Digital Cartographic Data Standards, Columbus, Ohio. 
Nyerges, T.L. 1991. Representing Geographical 
Meaning. In: Buttenfield, B.P. & McMaster, R.P. Map 
Generalization: Making Rules for Knowledge 
Representation. Longman Scientific & Technical, Bath 
Press, Avon, pp. 59-85. 
Sowa, J.F. 1984. Conceptual structures. Information 
processing in mind and machine. Addison-Wesley 
Publ. Co. 
It" 
Urban, S.D. & Delcambre, L.M.L. 1990. Constraint dict 
Analysis: A design Process for Specifying Operations 
on Objects. IEEE Trans. Knowledge and Data 
Engineering, 2 (4) : 391-400. 
fun 
(m 
mot 
White, M.S. 1984. Technical Requirements and rela 
Standards for a Multipurpose Geographic Data System. date 
The American Cartographer, 11 ( 1) : 15-26. rela 
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