Evidence of breakdown of the spin symmetry in diluted 2D electron gases P. Giudici, A. R. Goñi, P. G. Bolcatto, C. R. Proetto, C. Thomsen, K. Eberl and M. Hauser EPL, 77 3 (2007) 37003 Published online: 01 February 2007 DOI: 10.1209/0295-5075/77/37003