Maps 593 Observations 20 Databases 14 Statistics 13 Bibliographies 7 Bibliography 7 Conference papers and proceedings 7 Congresses 7 Surveys 4 Festschriften 3 Periodicals 2 Tables 2 Academic theses 1 Atlases 1 Biographies 1 Biography 1 Catalogs 1 Charts, diagrams, etc 1 Computer network resources 1 Directories 1 Encyclopedias 1 Geographic information systems 1 Globes 1 Graphs 1 Handbooks and manuals 1 Handbooks, manuals, etc 1 History 1 Remote-sensing maps 1 Serial publications 1 Software 1 Tables (Data) 1 Topographic maps 1 World maps 1