Astanga Hrudaya
नाभेरूर्ध्वं मुखात्पक्वाः प्रस्रवन्त्यधरे गुदात् । गुदास्यान्नाभिजो विद्याद्दोषं क्लेदाच्च विद्रधौ ॥ १७ ॥
After ripening, the abscesses localized above the umbilicus expel their contents (pus, blood etc) through the mouth, those localized below the umbilicus, though the rectum.Those localized in the umbilicus expel their contents through both rectum and mouth.
english translation
nAbherUrdhvaM mukhAtpakvAH prasravantyadhare gudAt । gudAsyAnnAbhijo vidyAddoSaM kledAcca vidradhau ॥ 17 ॥
hk transliteration by Sanscript