SYNTHESIS AND PROPERTIES OF NEMATIC LIQUID CRYSTALS EXHIBITING A POSITIVE DIELECTRIC ANISOTROPY V.V. TITOV, E.I. KOVSHEV, A.I. PAVLUCHENKO, V.T. LAZAREVA et M.F. GREBENKIN J. Phys. Colloques, 36 C1 (1975) C1-387-C1-392 DOI: 10.1051/jphyscol:1975163