Wikipedia:Articles for deletion/Zipper theorem
as the entry and comment immediately above combine to show this is a non-otability|notable mathematical exercise (and the solution may be |original research). No evidence that this theorem has any role except as a textbook exercise in a single textbook, and OTTEXTBOOK|Wikipedia is not a textbook. Could possibly consider a transwiki to Wikiversity or Wikibooks but i'd be wary of the copyright implications of taking an exercise from a published book
— User:Qwfp, 10:18, 17 July 2009 (UTC)
Stance: delete
Cited policy: WP:N||WP:NOTTEXTBOOK||WP:original research (Wikipedia:Notability)