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Picard, Jean 1921-, Arpád Péter 1944- Orbán, Giorgio Beltrutti, James 1931-2018 Hogg, and Kent 1944- Emery. Miscellanea Cartusiensia: 4. La Chronique "Quae in Posterum" De Bernard D'Ambronay; Heinrich Von Kalkar, Theoria Metrica; The Carthusians, Intermediaries for the Teaching of John Ruysbroeck During the Period of Early Reform and in the Counter-reformation; Giorgio Beltrutti's La Certosa Di Pesio. Salzburg: Universität Salzburg, 1979.

Picard, Jean 1921-, et al. Miscellanea Cartusiensia: 4. La Chronique "Quae in Posterum" De Bernard D'Ambronay; Heinrich Von Kalkar, Theoria Metrica; The Carthusians, Intermediaries for the Teaching of John Ruysbroeck During the Period of Early Reform and in the Counter-reformation; Giorgio Beltrutti's La Certosa Di Pesio. Salzburg: Universität Salzburg, 1979.