I edited this answer so that the referenced books would now have links to their respective pages on Amazon should any user decide to purchase the books.
I assume that the original answerer is not affiliated with either work. Is this okay to do to answers? (Or questions too, I guess)
ISBN's are the easiest way to uniquely identify a book.
Instead of a seller site, I'd link to an ISBN lookup, like this. Or maybe link to a google books lookup of the ISBN like this. The beauty of these two is that they in no way support the author or push the book itself. Clicking into them will solely get you more information on the novel (or an avenue to purchase/find more about the author if you so desire).
I think secondary to this would be a third party website like wikipedia. And lastly would be an author or book website like Ælis mentions, if you can confirm that they are legitimate. But like seller sites, these usually have some amount of traffic tracking that users may not want to unknowingly jump into.
Regardless of what you choose, I do think we should try to avoid directly linking to seller sites.
I think it was nice that you added those links, however, I'm not really comfortable with the idea of them leading to Amazon.
In such a situation, I think it would be best if we could:
If not possible:
If still not possible:
So, in this specific case, I believe we should link to this (author's website) and that (Wikipedia page of the autor) instead of Amazon.
