S. Schottl, E. Schuberth, K. Flachbart, J. Kycia, A. Menovsky: Penetration depth and torque of superconducting UPt3. 1999Physica B-Condensed Matter: 259-61. ISBN 0921-4526 http://dx.doi.org/10.1016/S0921-4526(98)01076-X