One of the last two series (N and O) printed in Cracow, at Zaklady Graficzne "Sztuka", and not in Vienna as the earlier ones. It differs in the typeface used to mark the series. Listed in Czesław Miłczak's catalog as a separate variety.
The N series was distinguished by Michal Bishop as the second lowest-circulation item from the German occupation period in his book "Banknotes My Passion - Notebook I".
