Equational Theories Generated By Hypersubstitutions of Type (n). - Klaus Denecke; Jörg Koppitz; Staszek Niwczyk (Int. J. Algebra Comput., 2002)

Nonrepetitive colorings of trees. - Bostjan Bresar; Jaroslaw Grytczuk; Sandi Klavzar; Staszek Niwczyk; Iztok Peterin (Discret. Math., 2007)