Adolph Francis Alphonse Bandelier,
Catholic Encyclopedia
(1913)
“ In 1641 the Abipones had already obtained the horse from the Spanish settlers. At that time they were, according to tradition, still north of the Rio Bermejo, whence it is likely they were driven south by the Tobas, a warlike tribe of their own linguistic stock. Their horses, thriving on the grassy plains, soon made the Abipones very dangerous to Spanish colonization by means of raids on the settlements, by which they increased their own stocks of horses and cattle. ”
