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**1_introduction.tex
(./1_introduction.tex
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./1_introduction.tex:2: LaTeX Error: Missing \begin{document}.

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l.2 W
     e have to make sure, that either all operational participants commit the
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l.2 W
     e have to make sure, that either all operational participants commit the
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Here is how much of TeX's memory you used:
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./1_introduction.tex:2:  ==> Fatal error occurred, no output PDF file produced!