These data were recorded in gothic letters in a booklet entitled Parrows of Murillo el Fruit. It was preserved for a long time in the municipal archive of the locality and more than a century ago reached the Archivo Real y General de Navarra. Recently, the Maika Munariz archival technique has presented the document Peio J. It was taught to historian Monteano and, surprised by its content, they decided to investigate in depth the document – and the Navarrorum that goes from town to village. To present in the exhibition the heritage of two thousand years of Navarros documents about the Basque country.

The document had no date or signature, but it was concluded that it was from the beginning of the 15th century and that the author was Gil López de Sarasa, since at that time these functions corresponded to the notary of Olite. Monteano was surprised by the Basque toponyms that were collected in the document: There were also Romanesque toponyms (Malpuent, Parral or Tranca). Although the names in Euskera are more numerous, almost all have been lost.

Monteano immediately contacted Patxi Salaberri of Euskaltzaindia, who, after an exhaustive linguistic analysis, published the results in the journal Fontes Linguae Vasconum. In addition to the toponyms, Salaberri received several aliases in the Basque of the bats: Johan Biperr (mayor of the village in 1396), María Garizu, Per Arceiz Lucea, Salvador Ederra or García Zalduna.

Historians and linguists have so far considered that in the Middle Ages there was no talk in Basque in those villages where there is no toponymy in Basque. But, in the words of Monteano, “the book of the petxas of Murillo el Fruit demonstrates that in the sixteenth century the Basque language was a living language in the Ribera de Navarra”.