- Graph Theory,
- Molecular Graphs,
- Topological Graph Indices,
- Chemical Applications of Graph Theory,
- Spectral Graph Theory,
- Chromatic Polynomials,
- Digraphs,
- Graph Matrices,
- Number Theory,
- Elliptic Curves,
- Diophantine Equations,
- Discrete Groups,
- Modular Group,
- Hecke Groups,
- Regular Maps,
- p-adic Analysis,
- q-Calculus,
- Physical Mathematics.