AirForce:10.1209/0295-5075/93/37005
AirForce:10.1209/0295-5075/106/58002
AirForce:10.1209/epl/i1996-00246-4
AirForce:10.1209/epl/i1998-00509-0
AirForce:10.1209/epl/i2002-00516-1
AirForce:10.1209/epl/i2004-10340-1
AirForce:10.1209/epl/i2005-10106-3
AirForce:10.1209/epl/i2005-10371-0