Analysis of information sources in references of the Wikipedia article "인쇄기" in Korean language version.
Wolf, Hans-Jürgen (1974), 《Geschichte der Druckpressen》 1판, Frankfurt/Main: InterprintFrom old price tables it can be deduced that the capacity of a printing press around 1600, assuming a fifteen-hour workday, was between 3,200 and 3,600 impressions per day.