Thank you all for your replies,im glad you liked my review.
Roman > Im not really into that period,but i this is what is says below the picture "Most of the captured Wermacht equipment such as this Stug III with the tactical number 469 entered the 4th tank brigade,formed ad Osek. Ill open my other books today or tomorrow to see if i can post any additional info on that one

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Kozara is not really a museum, its is a military barrack.It was opened for public for some time,but now when the Republic of Serbia's military is organized it's not opened for public anymore.Here is a album with some photos from the time it was public.
http://s106.photobucket.com/albums/m273/nammeci/Muzej%20Kozara/#!cpZZ2QQtppZZ20Im pretty sure this is the reason?

Kind regards,Sven.
:-H