References Asea, P. and P. Zak (1999), \Time-to-build and cycles," Journal of Eco- nomic Dynamics and Control 23, 1155-1175. Benhabib, J. and A. Rustichini (1991), \Vintage capital, investment, and growth," Journal of Economic Theory 55, 323-339. Boucekkine, R., M. Germain and O. Licandro (1997), \Replacement echoes in the vintage capital growth model," Journal of Economic Theory 74, 333-348. Boucekkine, R., O. Licandro and C. Paul (1997), \Di®erential-di®erence equations in economics: On the numerical solution of vintage capital growth models," Journal of Economic Dynamics and Control 21, 347-362. Carroll, C., J. Overland and D. Weil (2000), \Saving and Growth with Habit Formation," American Economic Review 90(3), 341-355. Kolmanovskii, V. and A. Myshkis (1998), Introduction to the Theory and Applications of Functional Di®erential Equations. Kluwer Academic Publishers. Judd, K.L. (1998), Numerical methods in economics, The MIT Press. Paul, C. (1997), \A user-guide to Archi," Technical Report 283, Depart- ment of Mathematics, University of Manchester.