@article{Maciejewski:2009,
author
=
"A.Maciejewski and A.Nowicki",
title
=
"Algebras of constants for some extensions of derivations",
journal
=
"Indagationes Mathematicae",
volume
=
"Vol. 13",
number
=
"no 1",
pages
=
"77--88",
year
=
"2002",
}