Erdös Number

My (Delfim F. M. Torres) Erdös Number is at most 5, via the following path:

Another path, found using the MR Collaboration Distance project

1. MR1731420 (2000m:49048)
   Sarychev, A. V.; Torres, D. F. M.
   Lipschitzian regularity of minimizers for optimal control problems with control-affine dynamics.
   Appl. Math. Optim. 41 (2000), no. 2, 237--254.
    
2. MR0995286 (90i:93033)
   Agrachëv, A. A.; Gamkrelidze, R. V.; Sarychev, A. V.
   Local invariants of smooth control systems.
   Acta Appl. Math. 14 (1989), no. 3, 191--237.
    
3. MR0120437 (22:11191)
   Boltyanski, V. G.; Gamkrelidze, R. V.; Pontryagin, L. S.  
   Theory of optimal processes. I. The maximum principle. (Russian)
   Izv. Akad. Nauk SSSR. Ser. Mat. 24 1960 3--42.
    
4. MR1104655 (92f:52031)
   Boltyanski, Vladimir; Soifer, Alexander
   Geometric études in combinatorial mathematics.
   With introductions by Paul Erdös, Branko Grünbaum and Cecil Rousseau.
   Center for Excellence in Mathematical Education, Colorado Springs, CO, 1991.
   xii+236 pp.ISBN 0-940263-02-5
    
5. MR1330337
   Erdös, Paul; Soifer, Alexander
   Squares in a square.  Geombinatorics 4 (1995), no. 4, 110--114.

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