Ronalds, B.F. (2016). "Sir Francis Ronalds and the Electric Telegraph". International Journal for the History of Engineering & Technology. 86: 42–55. doi:10.1080/17581206.2015.1119481. S2CID113256632.
Ronalds, B.F. (2016). "Sir Francis Ronalds and the Electric Telegraph". International Journal for the History of Engineering & Technology. 86: 42–55. doi:10.1080/17581206.2015.1119481. S2CID113256632.