On nomenclature for, and the relative merits of, two formulations of   skew distributions
  We examine some distributions used extensively within the model-based clustering literature in recent years, paying special attention to} claims that have been made about their relative efficacy. Theoretical arguments are provided as well as real data examples. 
Adelchi Azzalini, Ryan P. Browne, Marc G. Genton and Paul D.   McNicholas
math.ST stat.CO stat.TH