1. Congenital absence of the azygos vein;Caggiati;76th Federative International Congress of Anatomy, Lisboa, abstract book,1994
2. Embriologia umana di Patten;Corliss,1981
3. Lumbar, renal and associated parietal and visceral veins based upon a study of 100 specimens;Davis;Surg Gyn Obstet,1958
4. Classification and calibration of the azygos venous system in 100 specimens;Falla;Surg Gyn Obstet,1963