Giovanni Vianini is obviously the cantor and director of the Schola Gregoriana Mediolanensis, in Milan; I'm not sure if that's his page (I think it is), or if it's a fan's page dedicated to him. The Canto Ambrosiano website says this about Vianini:
Giovanni Vianini, 62, of Cremona descents, begins his musical activity at 8 years old as cantor, contralto, in the Musical chapel of Milan's Chatedral managed by the Master Pietro Dentella.
Actually, he works in Milan in the liturgical sacred music field, vocal and instrumental. Organist and studious of organistic, he has built 30 organs with mechanical transmission, diversifing with the passing of time the own musical skill.
He devoted himself to the medieval music ( studying with the psaltery and the provenzal harp), to the Renaissance music, with the studying of the wind instruments ( chalmey, dulciana, cromorni and straight flutes).
His musical engagement is principally turned to the studying, divulgation and practice in liturgy of Ambrosian and Gregorian singing. He is Director of the Schola Gregoriana Mediolanensis chor, school instituited on 1981 and composed of 50 choristers. Every year he keeps a starting course to the Ambrosian and Gregorian singing ( with 100 members ).
For 10 years he has been Director of S. Marco Basilica Musical Chapel in Milan with the presence in several liturgical exhibithion and concerts of sacred music: besides he has organizes the " Gregorian Chant" and sacred polyphony review " Musical Spring" in S. Marco Basilica.
49 years of liturgical exhibithion as choir chorister, organist and choir director. Every second sunday of the month , the Schola Gregoriana Mediolanensis sings during the evening Mass at 6.00 p.m. in Chiaravalle Abbey in Milan with a Gregorian chant program.
Every fourth sunday of the month , the Schola Gregoriana Mediolanensis sings during the evening Mass at 6.30 p.m. in S. Marco Basilica in Milan with an Ambrosian chant program.
Anyway, there are dozens of videos there, and most are chant-oriented. Here's one labeled "TENEBRAE FACTAE SUNT, Responsorio ambrosiano" (an Ambrosian responsory, that is, I believe for Good Friday, but will look more at this):
[EDIT: I notice the video itself says this "Responsoria Settimana Santa," which I'm told means "Responsory for Holy Week." There's something there about "Feria VI. in Parasceve," too, and I'm not sure what that means. The chant score itself says that this is sung "After the Second Reading."]
[EDIT II: But then the note on the web page says this:
Responsorio ambrosiano per il Venerdi Santo, si trova a pagina 180 dell'Antifonale Ambrosiano edito da Desclee' e Socii (Roma?) Tournai, Belgium 1935. Schola Gregoriana Mediolanensis, solista e direttore Giovanni Vianini, Milano, Italia, www.cantogregoriano.it, studio del canto gregoriano ed ambrosiano, Polifonia medievale
And that says "Holy Friday," for sure. This was found in an Ambrosian Antiphonal, apparently.]
Anyway, the whole score is there, which is great.
HT to massinformation (I think that's where I saw it first, anyway).