The empty string Ø is the root vertex of T2 and for a vertex x of T2 the string x0 is the left child of x and the string x1 is the right child of x in T2.
Universal Music Group | Warner Music Group | Coxeter group | Volkswagen Group | Group of 77 | RTL Group | girl group | BT Group | ABB Group | Group One | Virgin Group | Thales Group | ING Group | group | Rio Tinto Group | Bloomsbury Group | Penguin Group | Carlsberg Group | Borders Group | Arup Group Limited | Benetton Group | Stagecoach Group | LMFAO (group) | Anschutz Entertainment Group | Tata Group | Rootes Group | Westfield Group | Group races | Group C | MTN Group |