Discussiones Mathematicae - General Algebra and Applications
Discussiones Mathematicae - General Algebra and Applications > 2006 > 26 > 2 > 233-251
Discussiones Mathematicae - General Algebra and Applications > 2008 > 28 > 1 > 91-119
Discussiones Mathematicae - General Algebra and Applications > 2006 > 26 > 2 > 233-251
Discussiones Mathematicae - General Algebra and Applications > 2008 > 28 > 1 > 91-119