Every person who passes by is a potential customer.

Before long, this box will be installed nearer Grosmont (NYM) level crossing to permit control of the crossing gates (presently hand-worked) and to replace the eight-lever ground frame which currently operates the pointwork.

We show that the signer can disavow any valid signature to the verifier. In other words, we show that the disavowal of their scheme is not uncheatable.

There's no new material on it, just previously issued bits and pieces. That rules out the completist collector. Go figure.