1. Bogdanović, S.,Semigroups with a system of subsemigroups, Inst. of Math. Novi Sad, 1985.
2. Bogdanović, S.,Inflations of a union of groups, Matematićki Vesnik37 (1985), 351–353.
3. Bogdanović, S.,Nil-extensions of a completely regular semigroup, Proc. of the Conf. “Algebra and Logic”, Sarajevo 1987, Univ. of Novi Sad 1989, 7–15.
4. Bogdanović, S. and M. Ćirić,A Nil-extension of a regular semigroup, Glasnik Matematički, Vol.25 (2) (1991), 3–23.
5. Bogdanović, S. and M. Ćirić,Retractive nil-extensions of regular semigroups, I, Proc. Japan Academy68A (5) (1992), 115–117.