See, for example, HallWilliam K., “SBU's: Hot New Topic in the Management of Diversification,”Business Horizon, Vol. 21 (February 1978); and HoferCharles W.SchendelDan, Strategy Formulation: Analytical Concepts (West Publishing, 1978).
2.
WrigleyLeonard, Divisional Autonomy and Diversification, unpublished doctoral dissertation, Harvard Business School (1970); RumeltRichard P., Strategy, Structure and Economic Performance (Harvard University Press, 1974).
3.
Return on total capital measures the returns available to both debt and equity investors. Hence, the financial leverage question of long-term debt to equity is eliminated from consideration.
4.
Interestingly, DEF's competitor adopted the portfolio concept in 1975, and, at the time of research, was busy implementing it.
