\documentclass[a5paper, 12pt]{book}
\usepackage{graphicx}
\usepackage[vmargin=20mm, textwidth=108.5mm, nofoot]{geometry}
\usepackage[autocompile]{gregoriotex}
\usepackage{polyglossia}
	\setdefaultlanguage{italian}
	\setotherlanguage{latin}
\usepackage{fontspec}
	\defaultfontfeatures{Ligatures={TeX}}
	\setmainfont[Numbers={Proportional,OldStyle}]{Arno Pro}
%%%%%%%%%%%

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\begin{document}

\gresetinitiallines{0}
\gabcsnippet{(c4) 1. Sal(e)ve(g) de(fe)cus(d) hu(f)má(e)ni(d) gé(c)ne(d)ris,(e.) (;) sal(c)ve(e) Vir(g)go(h) dí(j)gni(i)or(g) cé(h)te(f)ris,(g.) (:)
quæ(j) vír(j)gi(g)nes(h) om(g)nes(g) trans(f)gré(e)de(d)ris,(e.) (;) et(e) ál(c)ti(e)us(g) se(e)des(f) in(g) sú(h)pe(i)ris,(j.) (,) o(j) Ma(i)rí(kko>)a!(j.) <b><sp>R/</sp></b>.(::) <v>\kern 1em</v><i>Salve Mater.</i>()}

\end{document}
