\documentclass[letterpaper,12pt]{article}
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@article{article,
  author = {Nachname, Vorname and Zweiter, Zwentibold and Dritter, Dieter and Vierte, Veronika and Fünfter, Franz and Sechste, Sybille and Siebter, Siegfried},
  title = {Titel des Zeitschriftenartikels},
  journaltitle = {Zeitschrift},
  date = {2006},
  volume = {6},
  pages = {19-75}
}
@book{book2,
  author = {Autor, Alois and Nocheiner, Einar and Mustermann, Erik},
  title = {Ein anderes Buch},
  location = {Andershausen},
  date = {2011}
}

\end{filecontents}
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\begin{document}
\noindent
Erstes Zitat \parencite{article, book2}. Daraufhin folgt das zweite Zitat \parencite{article, book2}.

\printbibliography
\end{document}