I went today -- the clinic is what I would call behind the Palacio de Bellas Artes -- not on Maximo Gomez. The initials on the sign were GMA -- very easy to find the immunization department once you went inside and asked. Unfortunately, they did not have the combined Hepatitis A & B (twinrix) that I needed, just separate A & B. They also didn't have any suggestions on where else to go. So, I will probably just wait for my final dosage when I go to the US for the holidays or look for the one near the Plaza de la Salud.