EA. Schuberth, S. Schottl, K. Flachbart, T. Sasaki: DC magnetic penetration depth of UPt3 and Sr2RuO4: implications for the superconducting order parameters. 2001Journal of Magnetism and Magnetic Materials: 226. ISBN 0304-8853 http://dx.doi.org/10.1016/S0304-8853(00)00792-7