Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The order $p^8$ mesonic chiral Lagrangian   We derive the chiral Lagrangian at next-to-next-to-next-to-leading order
(NNNLO) for a general number $N_f$ of light quark flavours as well as for
$N_f=2,3$. We enumerate the contact terms separately. We also discuss the cases
where some of the external fields are not included. An example of a choice of
Lagrangian is given in the supplementary material.

31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
10
The categories of this paper are: q-bio
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an