Is this a different book or just a different edition?

[Stephanie]

I was looking up Speaking for Ourselves and Speaking For Ourselves Too: More Autobiographical Sketches by Notable Authors of Books for Young Adults, ed. Donald Gallo, but noticed they appear under the same title. I assumed the second one was a sequel, and therefore would be a separate book.

I can't confirm if they are entirely different content because I can't find a searchable copy online, but based on the intro to the latter ("There are dozens of other authors who were not included in that volume [Speaking For Ourselves] . . . which authors should be included in the next group?"), it seems like they are.

Basically, I'm looking for clarification on whether they should be separated or not, and why. It reminds me of The Bookfinder, whose 5 volumes are all listed separately, which is why I'm questioning whether this was an oversight or there's something I'm not getting about why they're combined.

[Scott]

They certainly look like two different books to me.