knitr - knitr block 的图形标题，包括 pdf 文档中的链接

Question

我有一个包含以下代码的小书本“书”:

A concept map is a diagram that shows 'ideas' and the relationship between those ideas. An example of a concept map is shown in Figure \@ref(fig:exampleCM).


```{r exampleCM, fig.show='hold', fig.cap='An example concept map --- Source: [Wikipedia](https://upload.wikimedia.org/wikipedia/commons/d/df/Conceptmap.png "Concept Map from Wikipedia")', echo=FALSE}                                  

knitr::include_graphics('images/ConceptMap.png')                                                                                                            
```                                                                                                                                                         

如果我将这本书呈现为 HTML，一切都会按预期进行。标题包括指向维基媒体/维基百科的超链接。即，标题看起来像这样:

Figure E.1: An example concept map — Source: Wikipedia

如果我将这本书呈现为 PDF，则 PDF 中的标题如下所示:

Figure E.1: An example concept map -- Source: [Wikipedia](https://upload.wikimedia.org/wikipedia/commons/d/df/Concep "Concept Map from Wikipedia")

由于某种原因，rmarkdown 似乎没有被渲染。生成的 LaTeX 文件是这样的:

A concept map is a diagram that shows `ideas' and the relationship between those ideas. An example of a concept map is shown in Figure \ref{fig:exampleCM}.

\begin{figure}
\includegraphics[width=12.33in]{images/ConceptMap} \caption{An example concept map --- Source: [Wikipedia](https://upload.wikimedia.org/wikipedia/commons/d/df/Conceptmap.png "Concept Map from Wikipedia")}\label{fig:exampleCM}
\end{figure}

我想知道我该如何解决这个问题。

Answer 1

Yihui Xie 上面的评论成功了。

感谢您提醒我有关文本引用的问题。