1. Incipit tractatulus venerabil[is] m[a]g[ist]ri Johannis Gerson cancellarij Parisiensis tractans de polluc[i]o[n]e nocturna an impediat celebrantem an non Author(s): Gerson, Jean, 1363-1429 Publication: [Cologne : Johann Guldenschaff, about 1480] Subject(s): EjaculationMoralsReligion and MedicineChristianity