INTERNATIONAL INSTITUTE 
FOR 
AERIAL SURVEY 
AND 
EARTH SCIENCES (ITC) 
DELFT, THE NETHERLANDS 
  
INVITED PAPER FOR COMMISSION VII 
S. A. HEMPENIUS 
PHYSIOLOGICAL AND PSYCHOLOGICAL ASPECTS 
OF PHOTO-INTERPRETATION 
  
ELEVENTH CONGRESS OF THE INTERNATIONAL SOCIETY FOR PHOTOGRAMMETRY. LAUSANNE 1968