Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Elliptic Singular Fourth Order Equations   Using a method developped in [1] and [2], we prove the existence of weak non
trivial solutions to fourth order elliptic equations with singularities and
with critical Sobolev growth.

15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin