A few books with missing(?) "date pub"

[Greg]

Hello -

I have a few books on my shelves that, when sorting by "date published", show "unknown". Is this just because of a missing "first published" date, or is there something else I should look at to discover what's happening?

If it's an obvious fix, here are the books that are doing this:

https://www.goodreads.com/book/show/2...

https://www.goodreads.com/book/show/2...

https://www.goodreads.com/book/show/2...

https://www.goodreads.com/book/show/2...

[Z-squared]

I'm guessing it was because they were missing an original publication date. I added those dates. Hopefully that fixes your sorting problem!