%0 Journal Article %A Zhou, Yishao %T On the phase portrait of the fast filtering algorithms %J ESAIM: Control, Optimisation and Calculus of Variations %D 1999 %P 609-630 %V 4 %I EDP-Sciences %U http://www.numdam.org/item/COCV_1999__4__609_0/ %G en %F COCV_1999__4__609_0