Discussion on "The track circuit as installed on steam railways"

H.M. Sayers, W.J. Thorrowgood, E.C. Irving, F. Gill, W. Duddell, A.H. Johnson, F.C. Raphael, J. Sayers, H.G. Brown
1907 Journal of the Institution of Electrical Engineers  
doi:10.1049/jiee-1.1907.0005 fatcat:b2zblbjqenacrek57bjw7utxne