there's a heading with elsarticle, and also with your code. It required that bibliography entries exist, otherwise there's no bibliography and no heading.
So ensure that there are entries.
If there are still problems, post a real

Stefan
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And: Currently, Packt sells ebooks for $4.99 each if you buy 5 of their over 1000 ebooks. If you choose only a single one, $9.99. How about combining 3 LaTeX books with Python, gnuplot, mathplotlib, Matlab, ChatGPT or other AI books? Epub and PDF. Bundle (3 books, add more for higher discount): https://packt.link/MDH5p
Code: Select all
\documentclass[12pt,a4paper,titlepage]{article}
\usepackage{amsmath}
\usepackage{amscd}
\usepackage{amsfonts}
\usepackage{inputenc}
\usepackage{amssymb}
\usepackage{makeidx}
\usepackage{graphicx}
\usepackage{lmodern}
\usepackage[english]{babel}
\usepackage{apacite}
\usepackage[round]{natbib}
\usepackage{hyperref}
\usepackage[all]{hypcap}
\hypersetup{
colorlinks=false,
linkcolor=blue,
filecolor=magenta,
urlcolor=cyan,
}
\urlstyle{same}
\begin{document}
\title{}
\author{,\footnote{}}
\maketitle
\begin{abstract}
\textbf{Key Words:}
\end{abstract}
\section{Introduction}
\section{Conclusion}
\bibliographystyle{apacite}
\bibliography{stability}
\end{document}
NEW: TikZ book now 40% off at Amazon.com for a short time.
And: Currently, Packt sells ebooks for $4.99 each if you buy 5 of their over 1000 ebooks. If you choose only a single one, $9.99. How about combining 3 LaTeX books with Python, gnuplot, mathplotlib, Matlab, ChatGPT or other AI books? Epub and PDF. Bundle (3 books, add more for higher discount): https://packt.link/MDH5p