Wikipedia:Articles for deletion/Perturbation training (2nd nomination)
offline sources are a real pain. That said, I'm going to  that they are legit.  If that's true, then the topic seems to pass  easily.  That it is primarily edited by one enthusiastic editor does not bother me unless it can be shown that there is some kind of policy violation that I am missing
— User:Paulmcdonald, 22:22, 8 May 2018 (UTC)
Stance: keep
Cited policy: WP:AGF||WP:GNG (Wikipedia:Assume good faith)