In Christian Europe, the first mention and representation of Hindu numerals (from one to nine), is in the Codex Vigilanus, a collection of several historical documents from the Visigothic period in Spain, written in the year 976 by three monks of the Riojan monastery of San Martin de Albelda.
Between 967 and 969, Gerbert of Aurillac discovered and studied Arab science in the Catalan abbeys. Once he became Pope Sylvester II in the year 999, he introduced a new model of abacus, known as the Abacus of Gerbert by utilising tokens representing Hindu numerals, from one to nine.
- Maths Origins, 2005