Francisco Gordillo's Erdös number

Erdös number is the number of "hops" needed to connect the author of a paper with the prolific late mathematician Paul Erdos. An author's Erdos number is 1 if he has co-authored a paper with Erdos, 2 if he has co-authored a paper with someone who has co-authored a paper with Erdos, etc. (Eric W. Weisstein. "Erdos Number." From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/ErdosNumber.html). The distribution of Erdös numbers is such that almost every mathematician with a finite Erdös number has a number of less than 8 - only about 2% are higher, and none is more than 15.

Visit the Erdös Number Project page for more information.

I'm not a mathematician but I have Erdös number. It is less or equal than 4. This is a path:

• Javier Aracil, Francisco Gordillo and Enrique Ponce, “Stabilization of Oscillations Through Backstepping in High-Dimensional Systems”, IEEE Trans. Automatic Control 50 (2005), no. 5, 705-710, 2005.
  
  
• Jaume Llibre and Enrique Ponce, "Global first harmonic bifurcation diagram for odd piecewise linear control systems", Dynam. Stability Systems 11 (1996), no. 1, 49--88.
  
  
• Joan Artés, Branko Grünbaum and Jaume Llibre, "On the invariant straight lines of polynomial differential systems", Planar nonlinear dynamical systems (Delft, 1995),  Differential Equations Dynam. Systems 5 (1997), no. 3-4, 317-327.
  
  
• Paul Erdös and Branko Grünbaum "Osculation vertices in arrangements of curves" Geometriae Dedicata 1 (1973), no. 3, 322--333.