Electrochromic and conductivity propertier: a comparative study between melanin-like/'V ind. 2''O ind. 5'.'nH ind. 2'O and polyaniline/ 'V ind. 2''O ind. 5'.'nH ind. 2'O hybrid materials - Oliveira, Herenilton Paulino; Graeff, Carlos Frederico de Oliveira; Brunello, Carlos Alberto; Guerra, Elidia Maria (Journal of Non - Crystalline Solids, 2000)