We would be grateful for assistance in obtaining copies of the following papers, particularly the first: S J Shepherd, "Cryptanalysis of the GSM A5 Cipher Algorithm", IEE Colloquium on Security and Cryptography Applications to Radio Systems, Digest No. 1994/141, Savoy Place, London, 3 June 1994, (COMMERCIAL-IN-CONFIDENCE). S J Shepherd, "An Approach to the Cryptanalysis of Mobile Stream Ciphers", IEE Colloquium on Security and Cryptography Applications to Radio Systems, Digest No. 1994/141, Savoy Place, London, 3 June 1994, (COMMERCIAL-IN-CONFIDENCE). S J Shepherd, "Public Key Stream Ciphers", IEE Colloquium on Security and Cryptography Applications to Radio Systems, Digest No. 1994/141, pp 10/1-10/7, Savoy Place, London, 3 June 1994. These are listed on Dr Shepherd's bio at: http://vader.brad.ac.uk/finance/SJShepherd.html