Antonov An-2 and An-3
The An-2 was developed after World War Two for agricultural
work.  It was such a success that it went on to perform other
roles, as a light-duty passenger and cargo aircraft. The An-3 is a
modification of the An-2 most notably the addition of a
turboprop engine.  It has the distinction of being the only biplane
designed and used for commercial purposes after WW2.
Above and below: An2.  Bottom of page: An-3