11: Battle at Kosovo Polje 550th Anniversary (1939)
12-15: International Car and Motor Races in Belgrade (1939)
16-19: 1939 Yugoslav Navy 20th Anniversary and Balkan States Postal Congress: Ships
20: King Alexander Assassination 5th Anniversary (1939)
1: 1939 King Peter II Definitives
2-6: Belgrade Postal Employees' Fund (1940)
7-11: Zagreb Postal Employees' Fund (1940)
12,13: Child Welfare (1940)
14: Balkan Entente 4th Anniversary (1940)
15,16: 1940 Airmail Set
17: 1940 Philatelic Exhibition in Zagreb and Printing Quincentenary (1)
18: 1940 Anti-Tuberculosis Fund (overprint on 1937 airmail set)
19-22: Ljubljana War Veterans Union and War Victims Monument Fund (1941)
23,24: 2nd National Philatelic Exhibition in Zagreb (1941)
Philatelic Exhibition in Slavonski Brod (1941):
(1) Printing
was first discovered and developed in China. The oldest surviving book printed
using the more sophisticated block printing dates from 868 AD. The movable
type printer was invented by Pi Sheng in 1040. The movable type metal printing
press was invented in Korea between 1234 and 1241. By the 12th and 13th century
many Arabic and Chinese libraries contained tens of thousands of printed books.
It is probable that Chinese printing technology diffused into Europe through
trade links that went through India and on through the Arabic world. Johann
Gutenberg developed European printing technology in 1440. Basing the design
of his machine on a wine press, Gutenberg developed the use of raised and
movable type and from the start used oil based inks. This development of the
printing press revolutionized the spread of knowledge.