错误 \pdfendlink 最终处于与 > \pdfstartlink 不同的嵌套级别

Question

在 ShareLaTeX 中编译此 tex 文件时，我收到以下错误：

English1213/LaTeX_English_def.tex（第 96 行）中的错误：pdfTeX 错误（ext4）：\pdfendlink 最终位于与 \pdfstartlink 不同的嵌套级别。\AtBegShi@Output ...ipout \box \AtBeginShipoutBox \fi \fi l.96 \end{document}

从我在文本中放置第二个 \citeA{} 命令开始，此错误就开始出现。当我仅使用 1 个\citeA{}命令进行编译时，没有任何问题……

有人可以帮我吗？

\documentclass[a4paper]{article}
\usepackage{StyleEN}

\usepackage{hyperref}
\usepackage{flushend}
\usepackage{graphicx}

\usepackage{amsmath,amssymb}
\usepackage[english]{babel}
\usepackage[numberedbib]{apacite}

% Title.
% ------
\title{FEASIBILITY STUDY OF HEAT NETWORK IMPLEMENTATION}


% Authors
% -------
\author{Peter Vanvoorden\supit{*}\\ \vspace*{0.25cm}
            \small{\supit{*}Master student $<$Biochemical Engineering$>$, GROUP T - Leuven Engineering College, Vesaliusstraat 13, 3000 Leuven \\ \vspace*{1.5cm}
            Supervisor(s): $<$Koen Pelsmaekers$>$ \\            
            Unit $<$Informatietechnologie$>$, GROUP T - Leuven Engineering College, Vesaliusstraat 13, 3000 Leuven, $<$\href{mailto:[email protected]}{[email protected]}$>$} \\ \vspace*{1em}
            Co-supervisor(s): $<$Stijn De Jonge\supit{1}, Dries Haeseldonckx\supit{2}, Nicolas Dosselaere\supit{3}$>$\\
            Coöperatief Ondernemen in Rationeel Energiegebruik (CORE) cvba-so, Naamsestraat 96, 3000 Leuven - Belgium\supit{1,2}\\ Nazka Mapps bvba, Ravesteinstraat 48A, 3191 Hever - Belgium\supit{3}
            }


\begin{document}

\input{TitlePageEN.tex}

%\pagebreak
\twocolumn

\section{Introduction}
\label{sec:intro}

Focusing on Belgium, statistics from \citeA{tradeco} point out that currently 97.51 \% of its population is living in urban areas while less than 1\% of them is connected to a DH network \cite{Euroheat1}. A study of \citeA{Santens} recapitulates the causes for this low adaptivity to three major categories: Economical, Institutional and Carbon-dioxide/Price related barriers. Within these, most emphasis is placed on following topics which could be considered potential fields of improvement: uncertainty of stable profits, non-recoverable costs in terms of existing individual and distribution infrastructure, a low priority and engagement from local governments, and the low availability of data concerning heat demand and heat supply.\\

%\renewcommand{\refname}{REFERENCES}
\bibliographystyle{apacite}
\bibliography{mybib}

\end{document}