Charak Samhita
वधबन्धप्रपतनाद्दंष्ट्रादन्तनखक्षतात् । आगन्तवो व्रणास्तद्वद्विषस्पर्शाग्निशस्त्रजाः ॥७॥
Exogenous ulcer are caused by blowing, binding, falling down, injury with fangs, teeth or nails as well as due to poisonous contact, fire and weapons etc.
english translation
vadhabandhaprapatanAddaMSTrAdantanakhakSatAt । Agantavo vraNAstadvadviSasparzAgnizastrajAH ॥7॥
hk transliteration by Sanscript