The Chord Keyboard

A keyboard prototype offers one-handed operation, small size, low cost of manufacture, and permits the touch typing of large alphabets.

PDF : https://s3.amazonaws.com/ieeecs.cdn.csdl.content/mags/co/1978/12/01646799.pdf?AWSAccessKeyId=ASIA2Z6GPE73KC4XEEFB&Expires=1598374533&Signature=M0jTNFcZPRnE0Gb%2BkfUi3zFTEP0%3D&x-amz-security-token=IQoJb3JpZ2luX2VjENj%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJIMEYCIQDHrdTvYBaNQQYcyPewcsANYIuPBKVs178%2FYZntvG6VNgIhAL7uh16BYeJ3Sfb5tDof03LBz6VCUY2i%2BHicZGC5sU0iKuABCMH%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEQABoMNzQyOTA4NzAwNjYyIgwQQyXPXKouE0YrW6wqtAFhNz9w5hpIWBd742UrBoLLFKH4vPfllcXulEaBXVnmMuGBXBQXKRW3s58xV3yPn9SXoa86OgL7SwyANdaqAlflZas1lqK1A3sg%2FVpVO4OwrcbO8PPE4NIt271CcQLyy9NL2fKpHUjbgi7ZmxElbVQzRZ9jIWk6wamd0Cf4L38ah%2Ba5K9sv%2B4At5zoqJ1%2B2qKcQldE9glvmIaZkXlx3SYIvtHPkBM0BGyeVaNrMEwdc%2BDr%2FKWsw8eSU%2BgU63wHlK25byYFs7TcgNrW7oMrbhyIABXnEyjBzmtbFDF9LYsaY9vKMRO5Up6%2Bm4%2F0TT9%2B%2FU8%2FdQgDW8rv59oega%2Bl8VnAP%2FdTsWIrzJUqr4zZrTa7UvwGD0GV8CDOgxEYNbJr8w3DRfSy%2BiAJ4CvZl5QHJBDrS93qF6WiKDiZgGP5K5INIhimwVDvjeRWax1aKQG6bSnWV2mCwi28n%2BSESr11hQr3kbMUwfBW1lXTx78KYa%2BpJokNpEt1%2B1Ek4se877n3GKOpKfj5GxpDBukOE0wygSpICG7%2Bn3g7zIxZoSLGZ

B-AIM