LaTeX Forum

\documentclass[ngerman]{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{babel}
\usepackage[autostyle,german=guillemets]{csquotes}

\usepackage[backend=biber, style=authoryear-ibid, autocite=footnote]{biblatex}

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\usepackage{filecontents}
\begin{filecontents}{\jobname.bib}
@online{burger,
  author  = {Kathrin Burger},
  title   = {Warum nehmen Essstörungen zu?},
  url     = {https://www.spektrum.de/news/essstoerungen-wie-magersucht-nehmen-zu/1439050},
  date    = {2017-02-24},
  urldate = {2019-10-05}
}
\end{filecontents}
\addbibresource{\jobname.bib}
\addbibresource{biblatex-examples.bib}

\begin{document}
Lorem\autocite{sigfridsson}
ipsum\autocite{burger}
dolor\autocite{nussbaum}
sit\autocite{worman}
amet\autocite{geer}.
\printbibliography
\end{document}

% Das ist mein LaTeX-Dokument.
\linespread{1.3}
\usepackage[backend=biber,style=authoryear-ibid, autocite=footnote]{biblatex}%style=authoryear-ibid
\addbibresource{Literatur.bib}
\usepackage[babel,german=guillemets]{csquotes}
\renewcommand*{\newunitpunct}{\addcomma\space}

@book{BeispielBuch,
    author    = "Mustermann {,} Max",
    title     = "Wie ich zur Musterfrau fand",
    series    ={International series of monographs on physics},
    publisher = "Musterverlag",
    year =      "2000",
    address   = " Musterstadt"

@online{spektrum,
    author  = "o. V.{,} 2017",
    title   = "Warum nehmen Essstörungen zu?",
    url     = "https://www.spektrum.de/news/essstoerungen-wie-magersucht-nehmen-zu/1439050",
    year     = "2017",
    urldate = {2019-10-05}