Michael Beenstock, Dalziel, Alan , and Warburton, Peter J. 1985. “Aggregate Investment And Output In The U.k.”. In Industrial Investment In Europe: Economic Theory And Measurement, Pp. 117 - 136. International Studies in Economics and Econometrics, vol. 12. http://search.ebscohost.com/login.aspx?direct=true&db=ecn&AN=0018256.