\documentclass{scrbook} \usepackage{mwe} \usepackage[T1]{fontenc} \usepackage[utf8]{inputenc} \usepackage{csquotes} \usepackage[ backend=biber, style=authoryear, ]{biblatex} \addbibresource{biblatex-examples.bib} \begin{document} \blindtext \footcite[S. 39][Vgl.]{aristotle:anima} \printbibliography[heading=subbibintoc] \end{document}
! Undefinded control sequence.
<argument> \blx@tempa