Jerome I see you never got around to this I m not surprised I looked for an example of the in nomine plainsong notaion and couldn t find one online to my astonishment too But maybe you could clear up a question for me is the cantus firmus of the English in nomines the plainchant in the alto part or one of Taverner s other three parts This is not clear to me in the article If the in nomines are based on the plainchant then where does Taverner come into it Your expertise would be most appreciated and maybe the article requires some explanation to this effect