"XXVI. Report of a Journey into the Batak Country, in the interior of Sumatra, in the year 1824. By Messrs. BURTON and WARD, Baptist Missionaries. Communicated by the late Sir STAMFORD RAFFLES, Kt.". Transactions of the Royal Asiatic Society of Great Britain and Ireland (dalam bahasa Inggris). Royal Asiatic Society of Great Britain and Ireland: The Society. 22 April 1826. hlm. 495.Parameter |url-status= yang tidak diketahui akan diabaikan (bantuan)
Greatheed, Samuel; Parken, Daniel; Williams, Theophilus; Conder, Josiah; Price, Thomas; Ryland, Jonathan Edwards; Hood, Edwin Paxton (1826). The Eclectic Review (dalam bahasa Inggris). C. Taylor. hlm. 428.Parameter |url-status= yang tidak diketahui akan diabaikan (bantuan)
"XXVI. Report of a Journey into the Batak Country, in the interior of Sumatra, in the year 1824. By Messrs. BURTON and WARD, Baptist Missionaries. Communicated by the late Sir STAMFORD RAFFLES, Kt.". Transactions of the Royal Asiatic Society of Great Britain and Ireland (dalam bahasa Inggris). Royal Asiatic Society of Great Britain and Ireland: The Society. 22 April 1826. hlm. 496–497.Parameter |url-status= yang tidak diketahui akan diabaikan (bantuan)