Mchombo, Sam (2008). «The Ascendancy of Chinyanja». I Brown, Keith; Ogilvie, Sarah. Concise encyclopedia of languages of the world. s. 793. «A recurrent joke in linguistics courses ... is the quip that ...»
Barfield, Thomas (1998). The Dictionary of Anthropology. «Fundamental notions such as 'language' and 'dialect' are primarily social, not linguistic, constructs, because they depend on society in crucial ways.»