Discussiones Mathematicae - General Algebra and Applications
Discussiones Mathematicae - General Algebra and Applications > 2006 > 26 > 1 > 75-83
Discussiones Mathematicae - General Algebra and Applications > 2011 > 31 > 2 > 185-199
Discussiones Mathematicae - General Algebra and Applications > 2006 > 26 > 1 > 75-83
Discussiones Mathematicae - General Algebra and Applications > 2011 > 31 > 2 > 185-199