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\bibitem{Lie:etal:soundness:2016} Liu G., Reisig W., Jiang C., 
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of Workflow Systems}. IEEE Access, vol. 4, pp. 4104-4118, 2016.

\bibitem{latex:symbols:2024} Pakin S.: \textit{The Comprehensive 
\LaTeX\ Symbol List}. 2024.\\ \url{https://ctan.org/pkg/comprehensive}
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