:::: WP:ELNO #1 only works because it is usually ignored in practice, it is meant to block spam and linkfarms (where it serves as "killer rule"), which we are not creating by adding those links, I agree however that there is a danger that people start linking all articles on MHP which might not be desired and getting us close to a link farm. However the real underlying question is here, whether we should create something like a "further reading" or "alternative reading" section. In which we list other comprehensive/recommendable treatments of the subject, that we'd recommend to readers (beyond their function as a source). Such would be books on the subject, treatments in other (encyclopedic) online sources, particularly extensive/comprehensive Artikels, etc.