- Non-integrability of the Painleve equations
- Analytic theory of the differential equations
- Stoyanova, Ts., Christov, O., Non-integrability of the Second Painleve equation as a Hamiltonian System, Compte Rendu de l'academie bulgare des sciences, vol. 60, 2007, p. 13-18.
- Horozov, E., Stoyanova, Ts., Non-integrability of some Painleve VI-equations and dilogarithms, Regular and Chaotic Dynamics, vol. 12, 2007, p. 620-627.
- Stoyanova, Ts,. Non-integrability of Painleve VI in the Liouville sense, Nonlinearity 22, 2009, p. 2201-2230.
- Stoyanova, Ts., Non-integrability of Painleve V equations in the Liouville sense and Stokes phenomenon, Advances in Pure Mathematics, vol.1, n.4, July 2011, pp. 170-183.
- Stoyanova, Ts., A note on the R.Fuchs's problem for the Painleve equations, http://arxiv.org/abs/1204.0157
- Tsvetana Stoyanova, Non-integrability of thr fourth Painleve equation in the Liouville-Arnold sense, Nonlinearity 27 (2014), pp.1029-1044.