Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Complete Integrability of a Nonlinear Elliptic System, Generating
  Bi-Umbilical Foliated Semi-Symmetric Hypersurfaces in $\R^4$   We find explicitly all bi-umbilical foliated semi-symmetric hypersurfaces in
the four-dimensional Euclidean space.

35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
34
The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
15
The categories of this paper are: nucl-ex
29
The categories of this paper are: funct-an