NIH:10.1209/0295-5075/81/68003
NIH:10.1209/0295-5075/82/48001
NIH:10.1209/0295-5075/116/24003
NIH:10.1209/epl/i2003-00107-2
NIH:10.1209/epl/i2004-10437-5
NIH:10.1209/epl/i2006-10204-8