[Answered] Publication date source

[Drace]

So I'm working on a cleanup thread for a book (big surprise!), and some of the editions listed on the publisher page are editions that are no longer in print and have been taken off of their publisher's website. Some of them are lacking a specific release date (they have month and year, but not day), so I wanted to ask before I work on the thread: would a "the book is out today!" announcement from the publisher's official Twitter account be enough proof to confirm a specific date, or is this not a good enough source?

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Giving this a bump.

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Bumping again.

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Bump.

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Bump for visibility.

[gem]

I would include a link to the month/year on the publisher website, and also include a link to the Twitter post specifying the exact date and leave it up to the Librarian adding/updating the book records to decide.

[Drace]

The editions in question are out of print and have had their pages removed from the publisher's website, but there is an archived version of the book's webpage available on the Wayback Machine. The website has the month and year, but not the day.

Thank you for your help, it's much appreciated.

BELATED UPDATE: Probably worth a mention that the correct publication date is listed in the Original Publication Date field for the book, but not in the individual edition publication date fields for the books.