“ Wikisource:Red link guidelines If the target page of an internal wikilink does not exist, it will appear red (unless the appearance has been changed through a user's preferences) , like this.
Sometimes it is useful in editing texts and other pages to create a red link to indicate that a page will be created soon or that an page should be created eventually. Red links show works and authors that could, and should, exist on Wikisource but are currently not present. ”

“ Cultural references that would have been well known to the contemporary audience can be obscure to modern readers. Authors of older works may also assume that their readers have studied Latin and Greek, which is less likely to be true now. ”

“ Third, if the file falls under fair use, you must not include it as fair use is prohibited on Wikisource and on Commons.
In regard to point 2, if a work mentions another work, the link should be to the main or Translation namespace rather than the Index or Page namespace. The same applies if a work mentions a section or passage of itself or another work. Anchors can be used where needed.
Unacceptable wikilinks Interpretative links (see below) are not acceptable. ”