On 1 July 1936, Košak joined the fledgling "Ustaše" and participated in starting of newspaper "Hrvatski narod" (The Croatian People).
He participated in starting of newspaper "Hrvatski narod" (The Croatian People). On 1 July 1936, Košak joined "Ustaše".
On 1 July 1936, Košak joined "Ustaše". He participated in starting of newspaper "Hrvatski narod" (The Croatian People).
On 1 July 1936, Košak joined "Ustaše". He participated in starting of newspaper "Hrvatski narod" (The Croatian People).