Temperature dependence of the electrical conductivity in 4,4′ bis(2-thenylideneamino)biphenyl and 4,4′ bis(thenyldiphenyl-phosphinylmethyleneamino)biphenyl compounds. - El-Sayed, B. A.; El-Nawawy, M. A.; Abd Ellah, E. M. (Journal of Materials Science, 1999)