
A generalization of the Euler's totient function and its applications, The days of the "Al. I. Cuza" University of Iaşi, October 2019.

O the ChermakDelgado lattice of a finite group, The days of the "Al. I. Cuza" University of Iaşi, October 2018.

The ChermakDelgado lattice of a finite group, The days of the "Al. I. Cuza" University of Iaşi, October 2017.

Criterii de comutativitate a grupurilor, Mathematics Teaching Seminar, Faculty of Mathematics, "Al. I. Cuza" University of Iaşi, March 2017.

A new poset associated to finite groups, The days of the "Al. I. Cuza" University of Iaşi, October 2016.

Sumfree sets in groups and hypergroups (with I. Tofan), The days of the "Al. I. Cuza" University of Iaşi, October 2015.

Subgroup commutativity degrees of finite groups, The days of the "Al. I. Cuza" University of Iaşi, October 2015.

Gradul de comutativitate al grupurilor finite, National Conference of SSMR, Iaşi, October 2014.

The posets of classes of isomorphic subgroups of finite groups, The days of the "Al. I. Cuza" University of Iaşi, October 2013.

Ireductibilitate în inele de polinoame, The days of the "Al. I. Cuza" University of Iaşi, October 2012.

Solitary quotients of finite groups, The days of the "Al. I. Cuza" University of Iaşi, October 2012.

Pseudocomplementation in (normal) subgroup lattices, The days of the "Al. I. Cuza" University of Iaşi, October 2011.

A probabilistic aspect of finite group theory, The days of the "Al. I. Cuza" University of Iaşi, October 2011.

A note on subgroup coverings of finite groups, The days of the "Al. I. Cuza" University of Iaşi, October 2009.

Finite groups determined by an inequality of the orders of their subgroups, The days of the "Al. I. Cuza" University of Iaşi, October 2009.

On the lattice of fuzzy subgroups of a finite group, The days of the "Al. I. Cuza" University of Iaşi, October 2008.

Elattices and their applications, The days of the "Al. I. Cuza" University of Iaşi, October 2006.

Complementation in normal subgroup lattices (a survey), The Annual Symposium on Mathematics Applied in Biology & Biophysics, "Ion Ionescu de la Brad" University of Iaşi, June 2006.

Complementation in subgroup lattices (a survey), The Annual Symposium on Mathematics Applied in Biology & Biophysics, "Ion Ionescu de la Brad" University of Iaşi, June 2006.

A generalization of the lattice concept and its applications, The days of the "Al. I. Cuza" University of Iaşi, October 2005.

A note on Udecomposable groups, The Annual Symposium on Mathematics Applied in Biology & Biophysics, "Ion Ionescu de la Brad" University of Iaşi, May 2005.

On the group of autoprojectivities of an abelian pgroup, Anniversary Symposion of "Gr. C. Moisil" Seminar, Iaşi, May 2005.

Lisomorphisms of groups, The days of the "Al. I. Cuza" University of Iaşi, October 2004.

On groups whose lattices of subgroups are pseudocomplemented, International Conference ECIT 2004, Iaşi, July 2004.

A special class of groups (Udecomposable groups), The Annual Symposium on Mathematics Applied in Biology & Biophysics, "Ion Ionescu de la Brad" University of Iaşi, May 2004.

Fundamental group lattices and applications, The days of the "Al. I. Cuza" University of Iaşi, October 2003.

An application of the group theory, International Conference SSIA 2003, Iaşi, September 2003.

Actions of finite groups on lattices, National School of Algebra, Eforie Nord, Constanţa, September 2003.

On the groups associated to genetic recombinations, The Annual Symposium on Mathematics Applied in Biology & Biophysics, "Ion Ionescu de la Brad" University of Iaşi, May 2003.

On the subgroup lattice of a semidirect product of finite cyclic groups, The days of the "Al. I. Cuza" University of Iaşi, October 2002.

On the subgroup lattice of an abelian finite group, International Conference ECIT 2002, Iaşi, July 2002.

Communications at Algebra Seminar, Faculty of Mathematics, "Al. I. Cuza" University of Iaşi.