UTF8 and BibTeX problems

Question

I laid last hands on my project. I added some sources. But than everything just blew up. Hopefully you can help me!

Here are the error(s):

! Package inputenc Error: Unicode char \u8:̈ not set up for use with LaTeX.
See the inputenc package documentation for explanation.
Type H <return> for immediate help.
...
l.6 ...das den Menschen die gestohlene Zeit zurü
ckbrachte : ein
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
! Package inputenc Error: Unicode char \u8:̈ not set up for use with LaTeX.
See the inputenc package documentation for explanation.
Type H <return> for immediate help.
...
l.7 Mä
rchen-Roman}.
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
! Package inputenc Error: Unicode char \u8:̈ not set up for use with LaTeX.
See the inputenc package documentation for explanation.
Type H <return> for immediate help.
...
l.8 \newblock Heyne, Mü
nchen, 1996.
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
)
AED: lastpage setting LastPage
[1
]
Package atveryend Info: Empty hook `BeforeClearDocument' on input line 85.
Package atveryend Info: Empty hook `AfterLastShipout' on input line 85.
(./videnskabsteori_1.aux)
Package atveryend Info: Empty hook `AtVeryEndDocument' on input line 85.
Package atveryend Info: Executing hook `AtEndAfterFileList' on input line 85.
Package rerunfilecheck Info: File `videnskabsteori_1.out' has not changed.
(rerunfilecheck) Checksum: F82BC2727126FD8867B6303A26AE863C;41.
)
Here is how much of TeX's memory you used:
29542 strings out of 493486
594360 string characters out of 3143550
636803 words of memory out of 3000000
32345 multiletter control sequences out of 15000+200000
13316 words of font info for 42 fonts, out of 3000000 for 9000
957 hyphenation exceptions out of 8191
56i,11n,55p,841b,795s stack positions out of 5000i,500n,10000p,200000b,50000s
Output written on videnskabsteori_1.dvi (1 page, 7872 bytes).

Here is my bibtex source

@Book{kragh,
 author = {Kragh, Helge},
 title = {Naturerkendelse og videnskabsteori: de uorganiske videnskabers filosofi og historie},
 publisher = {Aarhus Universitetsforlag},
 year = {2004},
 address = {Aarhus},
 isbn = {9788779341432},
 }

@Book{momo,
 author = {Ende, Michael},
 title = {Momo oder Die seltsame Geschichte von den Zeit-Dieben und von dem Kind, das den Menschen die gestohlene Zeit zurückbrachte : ein Märchen-Roman},
 publisher = {Heyne},
 year = {1996},
 address = {München},
 isbn = {978-3-453-11813-3}
 }

@Book{sander,
 author = {},
 title = {Regeringens handlingsplan Nye veje mellem forskning og erhverv - fra tanke til faktura},
 publisher = {Ministeriet for Videnskab, Teknologi og Udvikling},
 year = {2003},
 address = {City},
 isbn = {87-91258-72-3}
 }

@MISC{spiegel,
  AUTHOR       = "Ina Brzoska",
  TITLE        = "Pharma-Firmen an der Uni: Künftige Ärzte trainieren ihr Lobby-Immunsystem",
  YEAR         = "2010",
  MONTH        = "November",
  HOWPUBLISHED = "Website",
  NOTE         = "          \url{http://www.spiegel.de/unispiegel/studium/lobbyismus-medizinstudenten-wehren-sich-gegen-die-pharmaindustrie-a-868977.html}; besøgt den 13. april 2015."
}

And here is my source code

\documentclass[a4paper]{article}
\usepackage[utf8]{inputenc}
\usepackage[ngerman, danish]{babel}
\usepackage[left=2cm,right=2cm,top=2cm,bottom=2cm]{geometry}
\usepackage[T1]{fontenc}

%Cite
\usepackage{tikz}
\usetikzlibrary{backgrounds}
\makeatletter

\tikzset{%
  fancy quotes/.style={
    text width=\fq@width pt,
    align=justify,
    inner sep=1em,
    anchor=north west,
    minimum width=\linewidth,
  },
  fancy quotes width/.initial={.8\linewidth},
  fancy quotes marks/.style={
    scale=8,
    text=white,
    inner sep=0pt,
  },
  fancy quotes opening/.style={
    fancy quotes marks,
  },
  fancy quotes closing/.style={
    fancy quotes marks,
  },
  fancy quotes background/.style={
    show background rectangle,
    inner frame xsep=0pt,
    background rectangle/.style={
      fill=gray!25,
      rounded corners,
    },
  }
}

\newenvironment{fancyquotes}[1][]{%
\noindent
\tikzpicture[fancy quotes background]
\node[fancy quotes opening,anchor=north west] (fq@ul) at (0,0) {``};
\tikz@scan@one@point\pgfutil@firstofone([email protected])
\pgfmathsetmacro{\fq@width}{\linewidth - 2*\pgf@x}
\node[fancy quotes,#1] (fq@txt) at ([email protected] west) \bgroup}
{\egroup;
\node[overlay,fancy quotes closing,anchor=east] at ([email protected] east) {''};
\endtikzpicture}

\makeatother

%MINT-pakker
\usepackage{amsmath, amsfonts, amssymb}
\usepackage{graphicx}
\usepackage{chemfig, chemmacros}
\usepackage[version=3]{mhchem}
\usepackage{multicol}
\DeclareMathOperator\erf{erf}

%Hyperlinks
\usepackage[hidelinks]{hyperref}
\urlstyle{rm}

%Caption
\usepackage[labelfont=bf]{caption}

%Header/Footer
\usepackage{fancyhdr}
\pagestyle{fancy}
\usepackage{lastpage}

\begin{document}



\section{Kilder}

\bibliography{kilder}
\bibliographystyle{plain}


\end{document}

Hopefully you can help me?

Kind regards and thank you very much in advance!

Answer 1

(Too long for a comment, hence posted as an answer.)

If I include the instructions \usepackage[utf8]{inputenc} and \usepackage[T1]{fontenc} in the preamble, I am unable to reproduce the errors you report having encountered, using the bib entries you posted. You may want to check your editor's input encoding settings, just in case these settings involve an encoding that's not UTF8.

\RequirePackage{filecontents}  % just for this example
\begin{filecontents}{kilder.bib}
@Book{kragh,
 author = {Kragh, Helge},
 title = {Naturerkendelse og videnskabsteori: de uorganiske videnskabers filosofi og historie},
 publisher = {Aarhus Universitetsforlag},
 year = {2004},
 address = {Aarhus},
 isbn = {9788779341432},
}

@Book{momo,
 author = {Ende, Michael},
 title = {Momo oder Die seltsame Geschichte von den Zeit-Dieben und von dem Kind, das den Menschen die gestohlene Zeit zurückbrachte: Ein Märchen-Roman},
 publisher = {Heyne},
 year = {1996},
 address = {München},
 isbn = {978-3-453-11813-3}
}

@Book{sander,
 author = {Sander},
 title = {Regeringens handlingsplan Nye veje mellem forskning og erhverv - fra tanke til faktura},
 publisher = {Ministeriet for Videnskab, Teknologi og Udvikling},
 year = {2003},
 address = {City},
 isbn = {87-91258-72-3}
}

@MISC{spiegel,
  AUTHOR       = "Ina Brzoska",
  TITLE        = "{Pharma-Firmen an der Uni: Künftige Ärzte trainieren ihr Lobby-Immunsystem}",
  YEAR         = "2010",
  MONTH        = "November",
  HOWPUBLISHED = "Website",
  NOTE         = "          \url{http://www.spiegel.de/unispiegel/studium/lobbyismus-medizinstudenten-wehren-sich-gegen-die-pharmaindustrie-a-868977.html}; besøgt den 13. april 2015."
}
\end{filecontents}

\documentclass[a4paper]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[ngerman, danish]{babel}
\usepackage[margin=2cm]{geometry}

\hyphenation{web-site} % default: web-si-te (arggh!)

%%%Cite
%%\usepackage{tikz}
%%\usetikzlibrary{backgrounds}
%%\makeatletter
%%
%%\tikzset{%
%%  fancy quotes/.style={
%%    text width=\fq@width pt,
%%    align=justify,
%%    inner sep=1em,
%%    anchor=north west,
%%    minimum width=\linewidth,
%%  },
%%  fancy quotes width/.initial={.8\linewidth},
%%  fancy quotes marks/.style={
%%    scale=8,
%%    text=white,
%%    inner sep=0pt,
%%  },
%%  fancy quotes opening/.style={
%%    fancy quotes marks,
%%  },
%%  fancy quotes closing/.style={
%%    fancy quotes marks,
%%  },
%%  fancy quotes background/.style={
%%    show background rectangle,
%%    inner frame xsep=0pt,
%%    background rectangle/.style={
%%      fill=gray!25,
%%      rounded corners,
%%    },
%%  }
%%}
%%
%%\newenvironment{fancyquotes}[1][]{%
%%\noindent
%%\tikzpicture[fancy quotes background]
%%\node[fancy quotes opening,anchor=north west] (fq@ul) at (0,0) {``};
%%\tikz@scan@one@point\pgfutil@firstofone([email protected])
%%\pgfmathsetmacro{\fq@width}{\linewidth - 2*\pgf@x}
%%\node[fancy quotes,#1] (fq@txt) at ([email protected] west) \bgroup}
%%{\egroup;
%%\node[overlay,fancy quotes closing,anchor=east] at ([email protected] east) {''};
%%\endtikzpicture}
%%
%%\makeatother

%%%MINT-pakker
%%\usepackage{amsmath, amsfonts, amssymb}
%%\usepackage{graphicx}
%%\usepackage{chemfig, chemmacros}
%%\usepackage[version=3]{mhchem}
%%\usepackage{multicol}
%%\DeclareMathOperator\erf{erf}

%Hyperlinks
\usepackage[hyphens]{url}
\urlstyle{rm}
\usepackage[hidelinks]{hyperref}

%%%Caption
%%\usepackage[labelfont=bf]{caption}

%Header/Footer
\usepackage{fancyhdr}
\pagestyle{fancy}

%%\usepackage{lastpage}

\bibliographystyle{plain}

\begin{document}
\nocite{*}
\bibliography{kilder}
\end{document}

Answer 2

If you use biblatex +biber (which understands utf8),it compiles fine.

Just add these lines to your preamble:

\usepackage{biblatex} 
\addbibresource{kilder.bib}

and replace at the end of the document:

\bibliography{kilder}
\bibliographystyle{plain}

with:

\nocite{*}
\printbibliography