Oh, it's Brennan on the Moor alright. Translate anything into another language and then back into the original and half of it won't make sense any more.

I don't know who Clive Griffin is; his book was only published around 15 years ago, so is hardly likely to be available on the web except via copyright thieves. Plenty of second-hand copies can be found for sale via this link, though:

Folk Music in Britain, Ireland and the USA.

I get the impression that it was a "pot boiler" and not very accurate or to be taken too seriously. You'd be better off looking at reliable sources.

Use the onsite search engine ("Lyrics and Knowledge Search" at the top of every page here) to find many references to Brennan on the Moor. You can also see several 19th century broadside texts at  Bodleian Library Broadside Ballads:

Brennan on the moor

Check out these references and you'll see what I mean.