Daintith, John (2008). tar. Oxford University Press (edisi ke-6th). doi:10.1093/acref/9780199204632.001.0001. ISBN9780199204632."Tar: Definition". Miriam Webster. Diakses tanggal 14 March 2013. "a dark brown or black bituminous usually odorous viscous liquid obtained by destructive distillation of organic material (such as wood, coal, or peat)".
"tar and pitch" (edisi ke-6th). The Columbia Electronic Encyclopedia. Diakses tanggal 14 March 2013. "tar and pitch, viscous, dark-brown to black substances obtained by the destructive distillation of coal, wood, petroleum, peat, and certain other organic materials. "
Lindqvist I., Lindqvist B., Tiilikkala K., Hagner M., Penttinen O.-P., Pasanen T. & Setälä H. (2010). "Birch tar oil is an effective mollusc repellent: field and laboratory experiments using Arianta arbustorum (Gastropoda: Helicidae) and Arion lusitanicus (Gastropoda: Arionidae)". Agricultural and Food Science19(1): 1-12. DOI:10.2137/145960610791015050.
infoplease.com
Daintith, John (2008). tar. Oxford University Press (edisi ke-6th). doi:10.1093/acref/9780199204632.001.0001. ISBN9780199204632."Tar: Definition". Miriam Webster. Diakses tanggal 14 March 2013. "a dark brown or black bituminous usually odorous viscous liquid obtained by destructive distillation of organic material (such as wood, coal, or peat)".
"tar and pitch" (edisi ke-6th). The Columbia Electronic Encyclopedia. Diakses tanggal 14 March 2013. "tar and pitch, viscous, dark-brown to black substances obtained by the destructive distillation of coal, wood, petroleum, peat, and certain other organic materials. "
merckvetmanual.com
Wickstrom, Mark. "Phenols and Related Compounds". The Merck Veterinary Manual. Merck Manuals. Diakses tanggal 16 April 2015.
merriam-webster.com
Daintith, John (2008). tar. Oxford University Press (edisi ke-6th). doi:10.1093/acref/9780199204632.001.0001. ISBN9780199204632."Tar: Definition". Miriam Webster. Diakses tanggal 14 March 2013. "a dark brown or black bituminous usually odorous viscous liquid obtained by destructive distillation of organic material (such as wood, coal, or peat)".
"tar and pitch" (edisi ke-6th). The Columbia Electronic Encyclopedia. Diakses tanggal 14 March 2013. "tar and pitch, viscous, dark-brown to black substances obtained by the destructive distillation of coal, wood, petroleum, peat, and certain other organic materials. "