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at Sofia, Plovdiv, Varna, Stara Zagora, Burgas etc. where 
specialists in geodetic, photogrammetric and cartographic 
processes are being trained. Their specialization is more 
practical and designed for topographic geodetic processing. 
Bulgaria had been a place for sterephotographic acti- 
vity and experimental territory as early as the beginning 
of the twentieth century, after the installation of the 
first sterephotogrammetric devices and stereoplotting 
apparatuses by Prof.K.Pulfrich and the Austrian engineer 
Eduard Von Orel. In the years 1907 and 1908 by the village 
Studena, Sofia district, there were taken surface stereo- 
photogrammetric pictures which later were worked out on 
the stereoautograph of Eng. Orel. There are publications 
concerning that work, in 1920 and 1925. At that time 
another land photogrammetric work was carried out ir the 
region of the Rhodopes and near Sofia. In 1928 engineer 
Bethold carried out some surface stereophotogrammetric 
work over 2.5 xm? near Bankya, Sofia district, with the 
purpose of introducing for the first time land phtogram- 
metry in working out topographic maps at scale 1:25 000 
by means of an analogue apparatus Wild autograph A 2. 
In 1935 for the working out the same map in the plain 
regions of the country there were commenced phototrans- 
formation procedures of airphotos in photoplans by 
phototransformers of the type Hugershoff-Heide.Stereo- 
plotting of aerophotos with analogue apparatus Wild and 
Zeiss for the map at scale 1:25 000 began in 1940, wile 
the maps at scale 1:5000 and the other larger scale pams were 
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