Is it permissible to read the books of Abdullah Al-Qasimi from before his apostasy, such as "The Struggle Between Islam and Idolatry" and "Problems of Hadith"?

One should consult scholars regarding reading books. If a book contains atheism, it is impermissible to read it merely for general knowledge, except for specialists who can refute falsehood. As for books free from atheistic ideas, there is no harm in reading them. And for someone who cannot ascertain the soundness of a particular book, it is better for him to occupy himself with the books of the Salaf.