Universidad Nacional de Colombia
        
    
    Author in the following contributions
- Flavor changing neutral currents beyond the Standard Model
 - Spontaneous Breaking and Flat directions in Supersymmetry
 - Constaints for a Z' boson with non-universal couplings in a supersimmetric model
 - Massive neutrinos and fermion mass hierarchy in a non-universal $U(1)_{X}$ extension with an invisible axion