Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Perturbations of periodic Sturm--Liouville operators
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
13
The categories of this paper are: quant-ph