1. Value of the electrocardiogram in identifying heart failure due to left ventricular systolic dysfunction;Davie;BMJ,1996
2. Niedermeyer E da Silva FL Electroencephalography: basic principles, clinical applications, and related fields Lippincott Williams & Wilkins 2005 http://books.google.co.uk/books?hl=en&lr=&id=tndqYGPHQdEC&oi=fnd&pg=PR11&dq=Electroencephalography&ots=GN5n2505tB&sig=1qpAzAXKhiHlXM727Obb3oJEsYA
3. Osiri M Welch V Brosseau L Transcutaneous electrical nerve stimulation for knee osteoarthritis (Review) 2009 http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD002823/pdf/standard
4. Electrocutaneous nerve stimulation-I: model and experiment;Butikofer;IEEE Trans Biomed Eng,1978
5. Functional electrical stimulation;Lynch;IEEE Control Syst,2008