Internal links in epublib on Android not working

I'm using the epublib Android library to read an existing EPUB and I can't seem to get the internal links to work.

One of the chapters has HTML like this

<a href="9781484702181.html">Click here</a>

      

        
        
        
      

    

but when you actually click on it you get the android web browser error:

The webpage at file:///data/data/com.temp.package/library/epub/9_epub_files/9781484702181.xhtml could not be loaded.

      

        
        
        
      

    

I tried changing the url like this but doesn't work.

<a href="./9781484702181.html">Click here</a>
<a href="OEPBS/9781484702181.html">Click here</a>

      

        
        
        
      

    

Is there something I need to do specifically to get the internal links to work?