Source: https://www.researchgate.net/profile/Pierre_Cattelain/publication/285895633_Early_radiocarbon_dates_for_Isturitz_Magdalenian_Pyrenees-_Atlantiques/links/569b839308aea14769540410/Early-radiocarbon-dates-for-Isturitz-Magdalenian-Pyrenees-Atlantiques.pdf