Discussiones Mathematicae - General Algebra and Applications
Discussiones Mathematicae - General Algebra and Applications > 2002 > 22 > 1 > 33-37
Discussiones Mathematicae - General Algebra and Applications > 2004 > 24 > 2 > 185-198
Discussiones Mathematicae - General Algebra and Applications > 2002 > 22 > 1 > 33-37
Discussiones Mathematicae - General Algebra and Applications > 2004 > 24 > 2 > 185-198