Symmetry of electrostatic interaction between pyrophosphate DNA molecules V. L. Golo, E. I. Kats, S. A. Kuznetsova and Yu. S. Volkov Eur. Phys. J. E, 31 1 (2010) 59-67 Published online: 20 January 2010 DOI: 10.1140/epje/i2010-10549-7