This website contains age-restricted materials including nudity and explicit depictions of sexual activity.
By entering, you affirm that you are at least 18 years of age or the age of majority in the jurisdiction you are accessing the website from and you consent to viewing sexually explicit content.
Could you share a link to that study?
I’ve done a little digging, I think it might be this book: Roger Hood, The Death Penalty: A World-wide Perspective.
It was mentioned at the end of this Amnesty International fact sheet (pdf) that it was first published in 1988 then updated, I think there was also a fifth edition in 2015 so maybe there’s an even another new one now. I’m not sure if this is exactly the same source I saw previously, but that could be because of the various revisions.
Thank you!