Simangunsong, E. H. ., A. N. . Pasaribu, and R. A. . Sembiring. “Directive and Commissive Speech in Roald Dahl Novel: The Umbrella Man”. Jurnal Pendidikan Dan Konseling (JPDK), vol. 4, no. 5, Oct. 2022, pp. 4265-76, doi:10.31004/jpdk.v4i5.7295.