Non-unique lifting of integer variables in minimal inequalities
  We explore the lifting question in the context of cut-generating functions. Most of the prior literature on this question focuses on cut-generating functions that have the unique lifting property. We develop a general theory for understanding the lifting question for cut-generating functions that do not necessarily have the unique lifting property. 
Amitabh Basu, Santanu S. Dey, and Joseph Paat
math.OC