TY - JOUR AU - M. Kankaanrinta TI - Lifting Smooth Homotopies of Orbit Spaces of Proper Lie Group Actions JO - Journal of Lie Theory PY - 2005 SP - 447 EP - 456 VL - 15 IS - 2 UR - http://geodesic.mathdoc.fr/item/JOLT_2005_15_2_a5/ ID - JOLT_2005_15_2_a5 ER -