\documentclass[a4paper]{article}
\usepackage[a4paper, total={20cm, 27cm}]{geometry}
\pagestyle{empty}
\usepackage[utf8]{inputenc}
\usepackage{hyperref}
\usepackage[
%backend=biber,
backend=bibtex,
style=alphabetic,
sorting=ynt
]{biblatex}
\addbibresource{/GW/root/bibtex/golem}
\title{The GOLEM tokamak bibliography}
\author{The tokamak GOLEM team}
%\date{}
\begin{document}
\maketitle
%IAEA.19
%\nocite{8876584,8876482,8824534,Dhyani_2019,JOFESvoboda2019,DhyaniEPS19,MachaEPS19}
%IAEA.20
\nocite{Novotny_2020,GRYAZNEVICH_2020,}
%\include{bibliography}
%\bibliographystyle{unsrt}
%\bibliographystyle{apalike}
%\bibliography{/GW/root/bibtex/golem,/GW/root/bibtex/others}
\printbibliography[title={Contributions}]
%\printbibliography[title={The tokamak GOLEM bibliography}]
\end{document}