@TECHREPORT{AmatoS02tr,
  author = {Gianluca Amato and Francesca Scozzari},
  title = {Optimality in goal-dependent Analysis of Sharing},
  institution = {Dipartimento di Informatica, Universit{\`a} di Pisa},
  year = {2002},
  number = {TR-02-06},
  month = may,
  key = {Abstract Interpretation, Logic Programming, Sharing},
  url = {http://compass2.di.unipi.it/TR/files/TR-02-06.ps.gz}
}