@conference{1425,
  author = {D. Lazzati},
  title = {GRB Progenitors and Environment (Invited Review)},
  year = {2005},
  address = {Rome, Italy},
  url = {http://arxiv.org/pdf/astro-ph/0505044v1.pdf},
  note = {JILA Pub. 7627},
}