Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Remarks on natural differential operators with tensor fields   We study natural differential operators transforming two tensor fields into a
tensor field. First, it is proved that all bilinear operators are of order one,
and then we give the full classification of such operators in several concrete
situations.

11
The categories of this paper are: hep-lat
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
3
The categories of this paper are: physics