#!/bin/bash
tr "áàâäãéèêëïíìîïóòôöõúùûüñÁÀÂÄÃÉÈÊËÍÌÎÏÓÒÔÕÖÚÙÛÜ Ççº,Ñ" \
   "aaaaaeeeeiiiiiooooouuuunAAAAAEEEEIIIIOOOOOUUUU_Cco_N" |\
   tr "
" "_" |\
   sed -e s/__/_/g -e s/ß/ss/g -e s/_-_/-/g