A few words about the model. Consider that the production function has complementary factors according to the following equation:we know that such an assumption is useful to engender fluctuations. The effective labor at the period is denoted but the working population is so that the labor rate is . The wage depends on the labor rate according to an assumption of the Philips curve type. The profits are entirely reinvested, they are equal to the savings and the part of profits in the global income is the complement of the part of wages so that . The labor depends on the capital according to . Then we have the systemThere is stationary state if , i.e., and
 ref. to Alain Goergen. "Dynamique Economique. Solutions de problèmes avec Maple et Matlab". Economica. 2006.
 ref. to Gilbert Abraham-Frois.