Optical linear polarization in ultra cool dwarfs - A tool to probe dust in the ultra cool dwarf atmospheresR. Tata, E. L. Martín, S. Sengupta, N. Phan-Bao, M. R. Zapatero Osorio and H. BouyA&A, 508 3 (2009) 1423-1427DOI: https://doi.org/10.1051/0004-6361/200911830