Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A note on the three dimensional sine--Gordon equation   Using a simple ansatz for the solutions of the three dimensional
generalization of the sine--Gordon and Toda model introduced by Konopelchenko
and Rogers, a class of solutions is found by elementary methods. It is also
shown that these equations are not evolution equations in the sense that
solution to the initial value problem is not unique.

3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math