Books on American English

Some books from my shelves that take on the American variant of English:

The American Language H.L. Mencken (1919, 1986)

A Dictionary of Americanisms on Historical Principles Mitford Mathews (1956)

Language in the USA Charles Ferguson and Shirley Brice Heath (1980)

Van Winkle's Return: Change in American English, 1966-1986 Kenneth G. Wilson (1987)

A Survey of Modern English Stephan Gramley and Kurt-Michael Pätzold (1992) [several chapters]