1. Arrow, K.J., et al., “Capital-Labor Substitution and Economic Efficiency”, Review of Economics and Statistics, 43 (1961), pp. 225–250.
2. Arrow, K.J., and M. Kurz, Public Investment, The Rate of Return, and Optimal Fiscal Policy, The Johns Hopkins Press, Baltimore, 1970.
3. Banks, H.T., and M.Q. Jacobs, “The Optimization of Trajectories of Linear Functional Differential Equations”, SIAM Journal on Control, 8 (1970), pp. 461–488.
4. Bate, R.R., “Optimal Control of Systems with Transport Lags”, Advances in Control Systems, Vol. 7, C.T. Leondes, ed., Academic Press, New York, 1969, pp. 165–224.
5. Blackburn, J.O., “An Optimal Unemployment Rate: Comment”, Quarterly Journal of Economics, 83 (1969), pp. 518–520.