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When using \cite{link1, link2, link3 etc} in my article, the output is [1,2,3], although it should be [1-3]. Can you tell me what is wrong in my code?
I use bibtex, and there is a sample of my code:

\documentclass[a4paper,fleqn]{cas-dc}
\usepackage[numbers]{natbib}
\bibliographystyle{elsarticle ...