1.- DIGITAL TERRAIN MODEL- THE BASIC SOURCE OF DATA FOR ANALYSIS AND DISPLAY OF WARTA RIVER VALLEY RELIEF AND COMPLEMENTARY ELEMENT OF DETAILED GEOLOGICAL MAP OF POLAND DATABASE BARCELONA: INST. CARTOGR. CATALUNYA, 1997 SECOND CONGRESS ON REGIONAL GEOLOGICAL CARTOGRAPHY AND INFORMATION SYSTEMS. BARCELONA, CATALONIA - SPAIN. JUNE 16TH - 20 TH, 1997. PROCEEDINGS Ver registro 2.- GEOLOGICAL COMPUTER MAPS IN POLAND BARCELONA: INST. CARTOGR. CATALUNYA, 1997 SECOND CONGRESS ON REGIONAL GEOLOGICAL CARTOGRAPHY AND INFORMATION SYSTEMS. BARCELONA, CATALONIA - SPAIN. JUNE 16TH - 20 TH, 1997. PROCEEDINGS Ver registro