Français : Sources :
Alistair Campbell (1959), Old English Grammar
Diarmaid Ó Muirithe (1978), The Anglo-Norman and their English Dialect of South-East Wexford
Joseph P. Crowley (1986), The study of old English dialects
J. Leclerc (2004), L'évolution de la langue anglaise
Joanna Bugaj (2004), Middle Scots Inflectional System in the South-west of Scotland
Raymond Hickey (2005), Dublin English: Evolution and Change
Jeremy Smith (2007), Sound Change and the History of English
Wayne Harbert (2007),The Germanic Languages
Arjen P. Versloot (2008), Mechanisms of Language Change: Vowel Reduction in 15th century West Frisian
Rolf Hendrik Bremmer (2009), An Introduction to Old Frisian
Jarich Hoekstra, Willem Visser, Goffe Jensma (2010), Studies in West Frisian Grammar
Michiel de Vaan (2011), West-Germanic *ai in Frisian
Richard M. Hogg (2011), A Grammar of Old English, Volume 1: Phonology
Patrick V. Stiles (2013), The Pan-West Germanic Isoglosses and the Subrelationships of West Germanic to Other Branches
Arjen P. Versloot (2014), The Runic Frisian vowel system: the earliest history of Frisian and Proto-Insular North Frisian
Frederik Kortlandt (2017), Old English and Old Frisian
Michiel de Vaan (2018), Historical Development of Dutch
Arjen P. Versloot (2019), Reduction of unstressed vowels in Proto-Frisian and the Germanic 'Auslautgesetze'
이재욱 (2020), (SET 총18권) 영국영어 사투리 전권 세트: 한국인을 위한 전세계 100가지 영어 사투리 영국 잉글랜드 영어기초+정통영어+북부영어+중부영어+동부영어+남부영어+런던영어 ALL SET
Livia Kaiser (2021), Runes Across the North Sea from the Migration Period and Beyond, An Annotated Edition of the Old Frisian Runic Corpus
Bernard Mees (2022), The English Language Before England, An Epigraphic Account
Glottolog (2022), Anglo-Frisian
Scotland's Census - Languages (2001-2011)
Ethnologue :