Generalised fine and Wilf's theorem for arbitrary number of periods. - Sorin Constantinescu; Lucian Ilie (Theor. Comput. Sci., 2005)

Fine and Wilf's Theorem for Abelian Periods. - Sorin Constantinescu; Lucian Ilie (Bull. EATCS, 2006)

The Lempel–Ziv Complexity of Fixed Points of Morphisms. - Sorin Constantinescu; Lucian Ilie (SIAM J. Discret. Math., 2007)