1. Emilie Dufresne, Jonathan Elmer, and Martin Kohls, The Cohen-Macaulay property of separating invariants of finite groups, Transform. Groups 14 (2009), no. 4, 771–785.[MR/doi]
  2. Martin Kohls, Invarianten zusammenhaengender gruppen und die Cohen-Macaulay eigenschaft, Master's Thesis, Technische Universitaet Muechen, 2005.
  3. Martin Kohls, Üeber die tiefe von invariantenringen unendlicher gruppen, PhD Thesis, Technische Universitaet Muechen, 2007.
  4. Martin Kohls, On the depth of invariant rings of infinite groups, J. Algebra 322 (2009), no. 1, 210–218.[MR/arXiv]