Frees, Craig (1991). "The Historiography of Dialectology"(PDF). Lore and Language. 10 (2): 67–74. Archived(PDF) from the original on 12 February 2018. Retrieved 11 February 2018.
Frees, Craig (1991). "The Historiography of Dialectology"(PDF). Lore and Language. 10 (2): 67–74. Archived(PDF) from the original on 12 February 2018. Retrieved 11 February 2018.
Clyne, Michael G. (1992). Pluricentric languages : differing norms in different nations. Clyne, Michael G., 1939-2010. Berlin. ISBN978-3110128550. OCLC858282330.{{cite book}}: CS1 maint: location missing publisher (link)