I have read almost every book from Sven Hassel.And i believe he is writing fiction.I dont remeber the first name of the author called Konsalik,but i have found very similar texts from Sven Hassels novels,what he claims as his personal experiences.Also he was supposed to be an member of an Tank crew and he claims of using panthers on the attack phase of the Operation Barbarossa.I would be very carefull to take his texts very seriously.