Subject: Liturgy
Title: Graduale
Subject: Canon Law
Author of work: Gregorius IX
Title: Decretales
Subject: Canon Law
Author of work: Gregorius IX
Title: Decretales
Subject: Liturgy
Title: Graduale
Subject: Canon Law
Author of work: Gregorius IX
Title: Decretales
Subject: Geography
Title: Geography
Subject: Theology
Author of work: Gregorius I
Title: Registrum
Subject: Canon Law
Author of work: Gratianus
Title: Decretum Gratiani
Subject: Canon Law
Author of work: Gregorius IX
Title: Decretales
Subject: Theology
Author of work: Augustinus
Title: In Genesim contra Manichaeos