Oh yes, I did, I must have deleted it in the trial and error process but even:
\newpage
\bibliographystyle{plain}
\bibliography{RefHT}
\renewcommand{\refname}{Bibliography}
\nocitesec{*}
\bibliographystylesec{plain}
\bibliographysec{RefHT}
\end{document}
generates the same, no bibliography appears.
Best
\K.