Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Neutrino oscillations in the framework of the tree-neutrino mixing   In the framework of the three-neutrino mixing the neutrino oscillations in
the atmospheric and solar ranges of neutrino mass-squared differences are
considered in the leading approximation. Neutrinoless double $\beta$- decay is
also discussed.

25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat