Bifurcations in Delay Differential Equations: an algorithmic approach in   frequency domain
  In this work we study local oscillations in delay differential equations with a frequency domain methodology. The main result is a bifurcation equation from which the existence and expressions of local periodic solutions can be determined. We present an iterative method to obtain the bifurcation equation up to a fixed arbitrary order. It is shown how this method can be implemented in symbolic math programs. 
Andrea Bel, Walter Reartes, Ana Torresi
math.DS