Topics
Electrostatics
This article was originally published online on 21 March 2012 with errors in the abstract, Eqs. (9), (19), and (29), and a misspelling of a name in the Acknowledgments section. AIP apologizes for these errors.
The article was correct as it appeared in the printed version of the journal. All online versions of the article were corrected on 29 March 2012.
© 2012 American Institute of Physics.
2012
American Institute of Physics