Hi Jeremy,
Unfortunately it is very complicated to tell which page a piece of
text comes from in an epub.
The problem is that the page size changes per device and also per
orientation.
A piece of text can for instance be on page 8 when I hold my phone
vertically, but it moves to page 7 when I hold it horizontally.
This because the viewer can put more text on the screen when I hold it
horizontally.
A possible solution is to not refer to a page but to a resource and a
position within that resource.
Example: chapter6.html, 17th character from the start.
regards,
paul