Internet History Sourcebooks Project
Fordham University: Medieval Sourcebook: Henry Iv Letter to Gregory Vii
Contains the full text of Henry IV's response to Gregory VII after being called a "usurper," in which Henry refers to Gregory IV as a "false monk."
Internet History Sourcebooks Project
Fordham University: Medieval Sourcebook: Ban on Lay Investitures
Contains the full text of Gregory VII's decrees which banned lay investiture.
Internet History Sourcebooks Project
Fordham University: Medieval Sourcebook: Lay Investitures Forbidden
Contains the full text of Gregory VII's decree banning investitures.