Michael  Beenstock. 1990. ?Exchange Rate Dynamics.?. In Current Issues In International Monetary Economics, Pp. 44 - 62. Hebrew U Jerusalem: Current Issues in Economics series, vol. 4. http://search.ebscohost.com/login.aspx?direct=true&db=ecn&AN=0282963.

Michael  Beenstock and Whitbread, Chris . 1990. ?Fixed Investment And The Technological Gap In The United Kingdom.?. Applied Economics, 22, Pp. 905 - 916. http://search.ebscohost.com/login.aspx?direct=true&db=ecn&AN=0233214.