@article{Borowiecki:2011,
author
=
"M.Borowiecki and K.Jesse-Józefczyk and E.Sidorowicz",
title
=
"The complexity of some acyclic improper colourings",
journal
=
"Discrete Mathematics",
volume
=
"Vol. 311",
number
=
"no 8-9",
pages
=
"732--737",
year
=
"2011",
}