Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Proper 3-orientations of bipartite planar graphs with minimum degree at
  least 3   We show that every bipartite planar graph with minimum degree at least 3 has
proper orientation number at most 3.

17
The categories of this paper are: q-fin
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
21
The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex