Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Comment on "Fe valency-induced effect on the magnetic and
  electrotransport properties in Nd$_{0.67}$Sr$_{0.33}$Mn$_{1-x}$Fe$_x$O$_3$
  polycrystalline system" [Appl. Phys. Lett. 82, 1721 (2003)]   Comment on "Fe valency-induced effect on the magnetic and electrotransport
properties in Nd$_{0.67}$Sr$_{0.33}$Mn$_{1-x}$Fe$_x$O$_3$ polycrystalline
system" [Appl. Phys. Lett. 82, 1721 (2003)]

9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ