1. Resultados Médicos Desarrollo e Investigación S.C., Pachuca, Hidalgo, Mexico
2. Clinical and Interventional Cardiology, Ajijic, Jalisco, Mexico
3. Private Practice, Puerto Vallarta, Jalisco, Mexico
4. Laboratorios Silanes S.A. de C.V., México City, Mexico
5. IMSS-Centro Médico Nacional Siglo XXI, México City, Mexico