 
      When trying to upload an EPUB to iBooks via iTunes Producer on the iTunes Store, if you encounter the following error:
ERROR ITMS-5107: “◯◯.epub: Fixed-layout books must supply a landmarks" at Book (MZItmspBookPackage)
Here’s what you need to do…
First, in the content.opf file, locate the line:
<item id="toc" properties="nav" href="nav.xhtml" media-type="application/xhtml+xml" />
Open the file specified in the nav, such as nav.xhtml or toc.xhtml.
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Then, structure it as follows:
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html >
<html xmlns:epub="http://www.idpf.org/2007/ops" lang="en" xml:lang="en" xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <title>Language Comic KATSUSHIKA HOKUSAI</title>
  </head>
  <body>
    <nav epub:type="toc" id="toc">
      <h1>contents</h1>
      <ol>
        <li>
          <a href=“◯◯.xhtml”>◯◯</a>
        </li>
      </ol>
    </nav>
    <nav epub:type="landmarks">
        <ol>
        <li><a href=“◯◯.xhtml" epub:type="cover">◯◯</a></li>
        <li><a href=“◯◯.xhtml" epub:type="bodymatter">◯◯</a></li>
        </ol>
    </nav>
  </body>
</html>
Ensure that within the nav element with epub:type=“landmarks”, there is an a element with epub:type=“bodymatter”.
ERROR ITMS-5107:...: Apple Support Communities