On the dimension of classifying spaces for families of abelian subgroups
  We show that a finitely generated abelian group $G$ of torsion-free rank $n\geq 1$ admits a $n+r$ dimensional model for the classifying space with isotropy in the family of subgroups of torsion-free rank less than or equal to $r\geq 0$. 
Ged Corob Cook, Victor Moreno, Brita Nucinkis, and Federico Pasini
math.GR math.AT