Carbon paste electrode modified with ascorbic acid and carbon nanotubes for determination copper in sugar cane spirit - Teixeira, M. C.; Tavares, E. F. L.; Saczk, A. A.; Okumura, L. L.; Cardoso, M. G.; Oliveira, Marcelo Firmino de; Magriotis, Z. M. (ECS Transations, 2012)