KHAN, Mumtaz Ahmad; ROUHI, Bijan. A study on a calculus for the Tk,x,y,z-operator. Pro Mathematica, [S. l.], v. 20, n. 39-40, p. 79–92, 2006. Disponível em: https://revistas.pucp.edu.pe/index.php/promathematica/article/view/10239. Acesso em: 28 dic. 2025.