This article has an erratum: [erratum]

Issue
EPL
Volume 98, Number 1, April 2012
Article Number 19001
Number of page(s) 6
Section Geophysics, Astronomy and Astrophysics
DOI http://dx.doi.org/10.1209/0295-5075/98/19001
Published online 13 April 2012

© EPLA, 2012