Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Quark-hadron duality for heavy meson mixings in the 't Hooft model
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
29
The categories of this paper are: funct-an
14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph
19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol