\documentclass[a4paper,12pt,BCOR=10mm]{scrreprt}
\usepackage[utf8]{inputenc}
\usepackage[ngerman]{babel}
\usepackage[T1]{fontenc}
\usepackage{scrpage2}
\pagestyle{scrheadings}
%\usepackage{floatflt}
%\usepackage{graphicx}
%\usepackage{multicol}
\usepackage{amsmath}
\usepackage{setspace}
\usepackage{hyperref}


% Title Page

\title{Lichtwellenleiter -- Theorie, Technik, Natur}
\author{Christoph Egger}

\chead{\headmark}
\cfoot{\pagemark}
\automark{chapter}

\begin{document}

\newcommand{\zB}{z.\,B.}

\maketitle

\tableofcontents
\onehalfspacing


\input{vorwort}

\input{historie}

\input{theorie}

\input{in_der_technik}

\input{in_der_natur}

\input{schluss}

\nocite*
\bibliography{main}{}
\bibliographystyle{alpha}

\end{document}