Algorithmic problems related to the direct product of groups. Božović, Nataša; Krstić, Sava — 1985 Publications de l'Institut Mathématique. Nouvelle Série
On Markov Properties Of Finitely Presented Groups Nataša B. Božović — 1977 Publications de l'Institut Mathématique
First Order Classes of Groups Having no Groups With a Given Property Nataša Božović — 1985 Publications de l'Institut Mathématique