http://www.revista.ingenieria.uady.mx/volumen15/sensor.pdf

http://www.analesranf.com/index.php/mono/article/viewFile/1068/1065

http://www.acredit.ece.buap.mx/_DOCUMENT%20COMPROBAT%20DE%20AUTOEVALUAC/17_IA%2045%20C.8.1.2/Memorias%20FCE/fmcelect/P-FMC-003.pdf

http://www.saber.ula.ve/bitstream/123456789/23848/1/s_menolasina.pdf