degree, this time from Sofia University, after completing his thesis, which was titled Hamiltonian systems and Abelian integrals.
[4] Among his best known mathematical works are "Versal deformations of equivariant vector fields for cases of symmetry of order two and three" (Ph.D. thesis, 1979), "On the number of limit cycles in perturbations of quadratic Hamiltonian systems" (joint with I. D. Iliev), "Some functions that generalize the Krall-Laguerre polynomials" (joint with F. A Grünbaum and L. Haine), and "Perturbations of the spherical pendulum and Abelian integrals".
He was the head of the Bulgarian National Science Fund until his resignation in February 2011 after suffering reprisals for combating corruption in the institution.
In this relation an open Letter addressed to the Rector Ivan Ilchev and the Members of the Academic Council of Sofia University “St.
Later the first instance Bulgarian court has decided that the act of Sofia University violates the law and that Professor Horozov must be returned to his job.