Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Simple proof of Zermelo's theorem   Most of the assertions in the theory of well ordered sets are quite simple.
However, one of its central statements, Zermelo's theorem, stands out of this
rule, for its well-known proofs are rather complicated. The aim of the current
paper is to propose a simple proof of this theorem. Please inform us if you
ever encountered such a proof.

6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc