\bib{1985/blakley} \yr 1985 \isbn 3--540--15658--5 \mr 86j:94003 \editor G. R. Blakley \editor David Chaum \book Advances in cryptology: CRYPTO '84 \series Lecture Notes in Computer Science \seriesvol 196 \publ Springer-Verlag \publaddr Berlin \endref