我的 latex 文档出了问题。当我使用下面的代码使用引理时，它在每个引理的末尾都显示一个小的黑色矩形。
\documentclass{IEEEtran}
\usepackage{eucal}
\usepackage{algorithm,algorithmic}
\begin{document}
\section{ Analysis}
This section discusses essential proofs of some of the properties explained in the earlier,\\
\newtheorem{theorem}{\textbf{Lemma}}
\begin{theorem}
Lemma statement 1
\end{theorem}
\begin{IEEEproof}
The body of the lemma.The body of the lemma. The body of the lemma. The body of the lemma. The body of the lemma.The body of the lemma.The body of the lemma. The body of the lemma. The body of the lemma.The body of the lemma.The body of the lemma. The body of the lemma.
\end{IEEEproof}
\newtheorem{theorem2}{\textbf{Lemma}}
\begin{theorem}
Lemma statement 2
\end{theorem}
\begin{IEEEproof}
The body of the lemma. The body of the lemma. The body of the lemma. The body of the lemma. The body of the lemma. The body of the lemma. The body of the lemma. The body of the lemma. The body of the lemma.
\end{IEEEproof}
\end{document}
上面的代码显示以下输出，
