" 

 :From the same guideline lower down is WP:NAMB, In many cases it is preferable not to have a hatnote when the name of the article is not ambiguous. Can't see that there would be any confusion when it is clearly disambiguated with the word 'book'. There are very many aircraft type monograph books with the name as the title, it would get very cluttered adding hatnotes to all of them. Hatnote is an editing guideline, not a policy.   "