Labor (2) Photography, Artistic (2) Fotografía (2) Trabajo (2) Voyages and travels (1) Trials (1) Survival (1) Statistics (1) Research (1) Reality (1) Production (Economic theory) (1) Pictures (1) Occupations (1) Maps (1) History (1) Hiking (1) Geography (1) Consumption (Economics) (1) Computer output microfilm devices (1) Chemistry, Analytic--Quantitative (1) Ordenadores--Salida en microfilme (1) Revista (1) Croquis (1) Sociedades geográficas (1) Imágenes (1) Territorio (1) Estudio (1) Realidad (1) Supervivencia (1) Procesos (1)