http://www.sec.gov/Archives/edgar/data/70502/000007050216000725/pps425.htm
http://www.sec.gov/Archives/edgar/data/70502/000007050216000726/fps424.htm
http://www.sec.gov/Archives/edgar/data/1000275/000114036116072665/form424b2.htm
http://www.sec.gov/Archives/edgar/data/883902/000114420416113249/v444235_424b3.htm
http://www.sec.gov/Archives/edgar/data/818686/000119312516649817/d207243d424b5.htm