International Workshop on Advanced Research in Geographic Information Systems Ascona, Switzerland, & Nievergelt, J. (1994). IGIS '94-- geographic information systems: International Workshop on Advanced Research in Geographic Information Systems, Monte Verita, Ascona, Switzerland, February/March, 1994 : proceedings. Springer-Verlag.
Chicago-viite (17. p.)International Workshop on Advanced Research in Geographic Information Systems Ascona, Switzerland, ja Jurg Nievergelt. IGIS '94-- Geographic Information Systems: International Workshop on Advanced Research in Geographic Information Systems, Monte Verita, Ascona, Switzerland, February/March, 1994 : Proceedings. Berlin: Springer-Verlag, 1994.
MLA-viite (9. p.)International Workshop on Advanced Research in Geographic Information Systems Ascona, Switzerland, ja Jurg Nievergelt. IGIS '94-- Geographic Information Systems: International Workshop on Advanced Research in Geographic Information Systems, Monte Verita, Ascona, Switzerland, February/March, 1994 : Proceedings. Springer-Verlag, 1994.