::I agree Lambert asserts that he was first published source, so this part is not totally original research. The verifiability (see wp:v) of his claim is questionable. Why should Wikipedia report Lambert's version without independant verification of his claims? He is not a recognised authority on academic or religious terminology. O'Brien is another primary source, she doesn't work for the OED, or any of the usual places we go to when we want an authorative answer to when terms originated. Also O'Brien does not directly credit Lambert so even this source doesn't directly support the article text. Also neither Lambert nor O'Brien state that the term was ever used to define "a style of Celtic Studies". What we really need is a citation that states that the Harvest magazine really was the first appearance.