The spectroscopic study of M8.5-M9.5 stars and brown dwarfs M.K. Kuznetsov, Y.V. Pavlenko and M.C. Galvez-Ortiz EPJ Web of Conferences, 47 (2013) 04002 Published online: 25 April 2013 DOI: 10.1051/epjconf/20134704002