Is the combination right

[Sylvia]

I added the Dutch translation Het vierde beest: God, de strijd om de wereldmacht en het einde van de oudheid and combined with the one mentioned in the topic.
When combining I found that there's another book with the title In the shadow of the sword, but its subtitle is different from the one mentioned in the official URL of the Royal Dutch library.
Here are the other editions I found. In the Shadow of the Sword: The Birth of Islam and the Rise of the Global Arab Empire This link refers to other already combined editions.

This all confused me, please help

[Renske]

Titles and subtitles are sometimes changed and as long as there isn't found some prove that it is not same edition it seems safe to me to combine them.

I see that you put the URLs of the Koninklijke Bibliotheek at the book pages, but personally I don't think those are according to the rules in the librarian manual

This field is for entering a URL officially associated with that book, such as a page on an author's site for the book. It may also be an author or publisher's website for the book, if it contains additional information or resources. Fan sites, reviews, book sellers, Wiki pages or other such pages should NOT be listed.

It isn't the author or publisher website and it doesn't give any additional information.

[Sylvia]

Renske wrote: "Titles and subtitles are sometimes changed and as long as there isn't found some prove that it is not same edition it seems safe to me to combine them.

I see that you put the URLs of the Koninklij..."

The reference to the Koninklijk Bibliotheek is accepted by GR as official reference, as there is no better source. Publisher websites references change too much certainly when a book is out of print.

[rivka, Former Moderator]

If there is no available official author link or publisher link, that field should be left blank. Libraries are good sources for the book data, but that's not what determines what goes in that field.

[Sylvia]

rivka wrote: "If there is no available official author link or publisher link, that field should be left blank. Libraries are good sources for the book data, but that's not what determines what goes in that field."

There was a list of all official country libraries after GR had to leave Amazon as a source. The official country library are a good source to find the official data that goes with the book.

[rivka, Former Moderator]

Correct. But again, the fact that a site is a good source is a completely separate question of whether it should be listed as the official URL for the book.

Libraries ARE good sources, but SHOULD NOT be listed as official links.

[Sylvia]

rivka wrote: "Correct. But again, the fact that a site is a good source is a completely separate question of whether it should be listed as the official URL for the book.

Libraries ARE good sources, but SHOULD ..."

OK I leave the field blank, because I'm not going to fill in a link to a publisher's site of which I know that in the near future we get a 404 warning because the link has vanished. Dutch publishers don't make perma links for their books.

BTW we left the discussion in the topic I added. I still don't know if the combining of the Dutch version with the English one I found was correct.

[rivka, Former Moderator]

Renske's response makes sense to me, and seemed like a sufficient answer.