How to link a pdf file in ePub 3?
i'm developing an ePub using Sigil.
I have addedd some PDF file in my Misc Folder.
Now i've created a link to that file, and everything is working fine with iBooks on my Mac.
But on iBooks for iOS7 when i tap the link it load (in overlay) a gray page, is this a bug?
Should i use another way for link the PDF?
This is probably an issue with iBooks for mac not really requiring strict ePub code. Many times things that "work" in iBooks for mac aren't actually compliant at all. I can't speak for Sigil directly, but can help with the ePub itself: I am guessing you need to change some things in your .opf file: you need to include the pdf as an item in your manifest AND as a nonlinear page in your spine: , .
You should use ePubcheck (https://github.com/IDPF/epubcheck) to make sure you are exporting a valid ePub.
If you need a tool to zip/unzip your ePub I would use this: http://www.mobileread.com/forums/showthread.php?t=55681