Centre for Lusophone and European Literatures and Cultures public high quality reference works in its field of expertise and complete works of pioneer sources of Portuguese and Lusophone culture and literature, such as works by Manuel Antunes, Mário Martins, Diogo de Teive and Fernão de Oliveira. Recent large scale projects by CLEPUL include "The Complete Works of Father António Vieira" and the complete pombaline works, both demanded by international scholars for many centuries. Other relevant projects include internationally recognized scientific works and recipient of prizes, such as: "Dicionário Temático da Lusofonia" [Thematic Dictionary of Lusophony] (2005), "Jardins do Mundo" [Gardens of the World] (2008), and "Dicionário Histórico das
Proto-Indo-European language concerning PIE since there is no written record of the language. PIE is estimated to have been spoken as a single language from 4500 BC to 2500 BC during the Late Neolithic to Early Bronze Age, though estimates vary by more than a thousand years. According to the prevailing Kurgan hypothesis, the original homeland of the Proto-Indo-Europeans may have been in the Pontic–Caspian steppe of Eastern Europe. The linguistic reconstruction of PIE has also provided insight into the culture and religion of its speakers. As Proto-Indo-Europeans became isolated from each other through the Indo-European migrations, the Proto-Indo-European language became spoken