The question is very basic: references to books ( or e-books or web published books ) or to state of art papers about current development trends for a strong-AI ?
Some points about this question (please, read them before close-vote):
It seems this site allows ask for references, see help center "reference requests for papers or text books" (several other stack exchange sites doesn't allows). Better do not include opinions about the books, just refer the book with a brief description.
Even when it is a very basic question, I've not found it already in this site (not a duplicate ?).
It is suppressing the small amount of books about the subject, after discard the ones related to applied AI, that is, discard Norvig book and similar, discard neural net ones (in all its variants, if target is an applied AI), ... . Discard also AGI proceedings, that contains papers that focus in very concrete aspects. Wikipedia describes some active investigation lines about AGI (cognitive, neuroscience, ...) but can not considered a educational/introductory resource.
Remark the point about development: not interested on philosophical questions about the risks of AI, its morality, ... if they are not related to its development. Development doesn't excludes mathematical foundation about it.
By example, if I look by example at this list "https://bigthink.com/mike-colagrossi/the-10-best-books-on-ai", the final candidates list became empty.