Šifra 777
From the cover of the book: "In the middle of 1963, nine armed and well-trained Ustashi terrorists were secretly introduced into our country: their intention was to cause a chaotic situation in the country through diversions and mass terror. Where were they trained? How were they recruited into the terrorist organization? Who pushed them into this a dangerous adventure? How and where did they cross the border and how were they caught?"
One copy is available