Two sons of French billionaire Laurent Dassault have stepped up to replace their father in managing conglomerate Groupe Industriel Marcel Dassault (GIMD), which manages a large chunk of the family’s $42 billion wealth.Two sons of French billionaire Laurent Dassault have stepped up to replace their father in managing conglomerate Groupe Industriel Marcel Dassault (GIMD), which manages a large chunk of the family’s $42 billion wealth. VnExpress English