1. Burke, M. J., andGleeson, D. T. (2000): ‘A micropower dryelectrode ECG preamplifier’,IEEE Trans. Biomed. Eng.,47, pp. 155–162
2. Chee, J. (2002): ‘Low-frequency high gain amplifier with high DC-offset voltage tolerance’. US patent, US6396343 B2
3. Dobrev, D. P., andDaskalov, I. K., (2002): ‘Two-electrode biopotential amplifier with current-driven inputs’,Med. Biol. Eng. Comp.,40, pp. 122–127
4. Dobrev, D. P. (2002): ‘Two-electrode biopotential amplieier’,Med. Biol. Eng. Comp.,40, pp. 546–549
5. Jorgovanovic, N., Petrovic, R., Dosen, S., andPopovic, D. (2001): ‘A novel AC amplifier for electrophysiology: active DC suppression with differential to differential amplifier in the feedback loop’.23rd Ann. Internat. Conf. IEEE EMBS, CD-ROM, paper 441.pdf