The database of 1524 working maps available here was taken from four “linguistic atlases” (AES, CLAE, LAE and WGE), all based on the "basic material" (i.e. the raw data presented in phonetic transcription) of the "Survey on English Dialects" (SED):

Kolb, Eduard / Glauser, Beat, / Elmer, Willy, and Stamm, Renate (eds.) (1979). Atlas of English Sounds, Bern: Francke.
Viereck, Wolfgang / Ramisch, Heinrich (eds.) (1991, 1997). The Computer Developed Linguistic Atlas of England, Tübingen: Niemeyer, 2 vols.
Orton, Harold / Sanderson, Stewart, and Widdowson, John (eds.) (1978). The Linguistic Atlas of England, London: Croom Helm.
Orton, Harold / Halliday, Wilfrid J. / Dieth, Eugen, and Wakelin, Martyn F. (eds.) (1962-1971). Survey of English Dialects. The Basic Material, Leeds: E. J. Arnold, 12 vols. (reprint: London: Routledge, 1998).
(See also online:
Orton, H., Wright, N. (eds.) (1974). A Word Geography of England, London, New York: Seminar Press.

These "linguistic atlases" do not contain raw materials - in contrast to romanistic "atlas linguistiques" (etc.) - but rather materials "authoritatively" pre-typed by the respective authors. We have taken exactly these typings (“taxations”) without any changes from the respective map works.

The 1524 working maps quoted at the beginning come from the four "linguistic atlases" considered by us as follows: AES: 424, CLAE: 597, LAE: 389, WGE: 114.

Of the 1524 working maps, 689 belong to phonetics (of which 511 to vocalism and 178 to consonantism) and 447 to lexicon (vocabulary).