Linked from
The 12 pages that link to Zorn's lemma, each with the reason it gives.
Well-ordering theoremRelated: It is equivalent to the well-ordering theorem in standard set theory.
Maximal idealRelated: Its application to proper ideals proves the maximal ideal theorem.
Tychonoff's theoremRelated: It is a common choice principle used in proofs of product compactness.
UltrafilterRelated: It proves that a proper filter can be extended to an ultrafilter.
Chain (order theory)Related: Its hypothesis is stated for all chains, including infinite ones.