Does divorce take effect by uttering explicit divorce pronouncements found in a book while reading it, especially if the reader does not recall whether he uttered them intentionally or not, and if what was intended was what was in the book, not the initiation of divorce?

Reciting the words of divorce for the purpose of study and learning does not constitute a divorce. The whispers (waswas) you mentioned do not result in divorce; therefore, ignore them and seek Allah's help. It is also recommended to consult the psychological counseling department.