Random triples
| Subject | Object |
|---|---|
| gptkb:USGS_1:63,360-scale_topographic_maps_of_Alaska | 15 minutes latitude by 15 minutes longitude |
| gptkb:One-inch_Map_series | varied by edition |
| gptkb:USGS_1:250,000-scale_topographic_map_series | 1 degree by 2 degrees |
| gptkb:Ordnance_Survey_Explorer | variable by region |