Hristo Kostov (1932-1982) [In Bulgarian]

This is an unpublished manuscript written in 1982 in memoriam of Hristo Kostov (d. November, 2nd, 1982), f. assistant professor at the University of Sofia. Hristo Kostov was a specialist in didactics of physics. He was known as one of the most successful physics teachers in Bulgaria. The building of the astronomical observatory in Belogradchik was his idea.