Every page number (or locator) must be a live link. In reflowable formats like EPUB, where "page 42" doesn't exist, these links point to specific anchors in the HTML code.
High-quality indexes use structured naming, such as: Orwell_George_Nineteen_Eighty-Four_1949_EPUB.epub Poor indexes use names like book123_final_FINAL_v2.pdf . index of ebooks high quality
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