King Roger II Martorana, Palermo ca. 1140

Ius commune enters papal letters Pope Alexander III (1159-1181)        4 letters 1169, 1171, 1171/1172,   1172 Pope Lucius III (1181-1185)        1 letter 1184-1185 Pope Urban III (1185-1187)         1 Letter 1185-1187 Pope Clement III (1187-1191)          1 Letter 1187 Pope Celestine III (1191-1198)