Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Regular canonical covers   We construct three sequences of regular surfaces of general type with
unbounded numerical invariants whose canonical map is 2-to-1 onto a canonically
embedded surface. Only sporadic examples of surfaces with these properties were
previously known.

18
The categories of this paper are: econ
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
17
The categories of this paper are: q-fin
7
The categories of this paper are: hep-th
14
The categories of this paper are: math-ph
4
The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
16
The categories of this paper are: stat