Mazliak, Laurent; Rainer, Catherine - In: Statistics & Probability Letters 62 (2003) 2, pp. 155-161
We prove that, given a closed set K and a controlled diffusion Xx,u, if, for all x[set membership, variant]K, there exists a control u such that the probability for Xx,u to stay some time in K is strictly positive, then K is viable for Xx,u.
