Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Theory and experiment of the ESR of Co$^{2+}$ in Zn$_2$ % (OH)PO$_4$ and
  Mg$_2$(OH)AsO$_4$
22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ
19
The categories of this paper are: eess
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
6
The categories of this paper are: astro-ph