\documentclass[a4paper, twocolumn]{article}
\usepackage{fontspec}
\setmainfont{Palatino Linotype}
\usepackage{setspace}
\setlength{\columnsep}{1cm}
\usepackage{paralist}
\usepackage{verbatim}
\usepackage[
sorting=none,
minbibnames=8,
maxbibnames=9,
block=space,
backend=biber
]{biblatex}
\bibliography{bibliography}
\usepackage{lipsum}
\begin{document}
\input{misc/title}
{
\setstretch{1.1}
\input{misc/abstract}
}
\newpage
\input{sections/introduction}
\input{sections/concept}
\input{sections/conclusion}
\section{References}
\nocite{*}
\printbibliography[heading=none]
\end{document}