Google search: languages with the word primitive in the name
High Resolution Paternal Genetic History of Ireland and its Implications for Demographic History
Scaled Innovation SNP Tree Explorer - Y DNA haplogroup R-Z39589
Large-Scale Migration into Britain During the Middle to Late Bronze Age
Bronze Age discovery reveals surprising extent of Britain’s trade with Europe 3,600 years ago
Pictish Language The Mysterious Ogham Inscriptions of Scotland
Scaled Innovation SNP Tree Explorer - Y DNA haplogroup R-BY228040 (Sweeney)
Scaled Innovation SNP Tree Explorer - Y DNA haplogroup R-FTA28478 (Sheehy)
The Big Tree - Y DNA haplogroup R-FT20439 (O’Donnell)
Scots Gaelic could die out within a decade, study finds | Scotland | The Guardian
Grammatica Celtica.. : Zeuss, J.K : Free Download, Borrow, and Streaming : Internet Archive
Graiméar na GaeDilge : Christian Brothers : Free Download, Borrow, and Streaming : Internet Archive
Complex politics or simple geography: Is Ireland part of the British Isles?
https://scaledinnovation.com/gg/treeExplorer.html?snp=R-FGC45278 (McDonald/O'Donnell)