Daintith, John (2008). "tar". A Dictionary of Chemistry (6th ed.). Oxford University Press. doi:10.1093/acref/9780199204632.001.0001. ISBN9780199204632. "Tar: Definition". Miriam Webster. Retrieved 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" (6th ed.). The Columbia Electronic Encyclopedia. Retrieved 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. "
Daintith, John (2008). "tar". A Dictionary of Chemistry (6th ed.). Oxford University Press. doi:10.1093/acref/9780199204632.001.0001. ISBN9780199204632. "Tar: Definition". Miriam Webster. Retrieved 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" (6th ed.). The Columbia Electronic Encyclopedia. Retrieved 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. "
"tar and pitch" (6th ed.). The Columbia Electronic Encyclopedia. Retrieved 14 March 2013.
"The terms tar and pitch are loosely applied to the many varieties of the two substances, sometimes interchangeably. For example, asphalt, which is naturally occurring pitch, is called mineral tar and mineral pitch. Tar is more or less fluid, depending upon its origin and the temperature to which it is exposed. Pitch tends to be more solid."
Daintith, John (2008). "tar". A Dictionary of Chemistry (6th ed.). Oxford University Press. doi:10.1093/acref/9780199204632.001.0001. ISBN9780199204632. "Tar: Definition". Miriam Webster. Retrieved 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" (6th ed.). The Columbia Electronic Encyclopedia. Retrieved 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. "
