Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Strong-coupling expansions for the anharmonic Holstein model and for the
  Holstein-Hubbard model
33
The categories of this paper are: plasm-ph
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
1
The categories of this paper are: cs
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex