Baerten, ‘Origines’, pp. 459-60. The primary record is Gestorum Abbatem Trudonensium Continuatio Tertia 1007, MGH SS X, p.382
dmgh.de
See for example Verhelst (1984, p. 248). A charter dated 24 Jan 1040 mentions a "county of Haspinga in the pagus Haspengouw", which had been the possession of count Arnold, understood to be the brother of Count Giselbert of Loon, also known as Arnulf. With this charter Emperor Henry III granted this county to the Cathedral of Saint-Lambert in Liège. (It can be seen at MGH DD H III 35 p.45 - comitatum Arnoldi comitis nomine Haspinga in pago Haspingowi.) Verhelst, Karel (1984), "Een nieuwe visie op de omvang en indeling van de pagus Hasbania (part 1)", Handelingen van de Koninklijke Zuidnederlandsche Maatschappij voor Taal- en Letterkunde en Geschiednis, 38
doi.org
Although all of the charters which describe the brothers as siblings of bishop Balderic II of Liège are later forgeries, there is considered to be enough evidence to be accept this relationship. There are many mentions of the relationship, and medieval forgeries were often wholly or partly based on older real documents. Kupper (1981): "Les documents qui éclairent les origines du prélat — documents diplomatiques faux ou suspects, sources narratives très tardives — sont loin d’offrir toutes les garanties. Nous estimons cependant que leur témoignage se fait l’écho d’une tradition basée sur la réalité." Vaes, following Baerten, emphasizes that in 1031, Bishop Reginard, Balderic II's successor, describes a grant made in the previous generation where Gislebert was named as both brother to Balderic and count of Loon. Kupper says that this document is also a false copy, though probably based on an older real act. "Cet acte est un faux qui se base probablement sur un document de 1026-1028" Kupper, Jean-Louis (1981), Liège et l'Église impériale aux XIe-XIIe siècles, Presses universitaires de Liège, doi:10.4000/books.pulg.1472, ISBN9782821828681
Although all of the charters which describe the brothers as siblings of bishop Balderic II of Liège are later forgeries, there is considered to be enough evidence to be accept this relationship. There are many mentions of the relationship, and medieval forgeries were often wholly or partly based on older real documents. Kupper (1981): "Les documents qui éclairent les origines du prélat — documents diplomatiques faux ou suspects, sources narratives très tardives — sont loin d’offrir toutes les garanties. Nous estimons cependant que leur témoignage se fait l’écho d’une tradition basée sur la réalité." Vaes, following Baerten, emphasizes that in 1031, Bishop Reginard, Balderic II's successor, describes a grant made in the previous generation where Gislebert was named as both brother to Balderic and count of Loon. Kupper says that this document is also a false copy, though probably based on an older real act. "Cet acte est un faux qui se base probablement sur un document de 1026-1028" Kupper, Jean-Louis (1981), Liège et l'Église impériale aux XIe-XIIe siècles, Presses universitaires de Liège, doi:10.4000/books.pulg.1472, ISBN9782821828681
