Sources

1) Source: The Henry Project . External Link
https://fasg.org/projects/henryproject/data/rober001.htm. Reference: Robert, archbishop of Rouen and count of Évreux (Questionable reliability of evidence)
2) Source: The Ecclesiastical History of England and Normandy: Volume III "For Richard, son of Gonnor, and duke of Normandy, was father of Robert I., whose son was William the Conqueror, the father of Duke Robert, who was father of William the Clito. On the other side, Robert the archbishop and count, who was brother of Duke Richard, had a son named Richard, count of Evreux, which Richard had a daughter called Agnes, wife of Simon, who bore Bertrade, Fulk's mother, and whose daughter Sibylla was." (Data from secondary evidence)
3) Source: The Henry Project . External Link
https://fasg.org/projects/henryproject/data/herle001.htm. Reference: Herleve (Questionable reliability of evidence)
4) Source: The Henry Project . External Link
https://fasg.org/projects/henryproject/data/richa002.htm. Reference: Richard, count of Évreux (Questionable reliability of evidence)