  In this paper, we prove that if a solution to the Muskat problem with
different densities and the same viscosity is sufficiently smooth, the solution
is analytic in a region that degenerates at the turnover points, provided some
additional conditions are satisfied. This paper studies the analyticity of the
solution near turnover points, complementing the result in $[$Jia Shi.
Regularity of solutions to the Muskat equation, Arch Rational Mech Anal 247, 36
(2023)$]$.
