"Jespersen 'A Modern English Grammar on Historical Principles' 1909-49 2:99"
"Mustanoja 'A Middle English Syntax' 1960, 438"
"Kisbye 'An Historical Outline of English Syntax' 1972, 133"
"Traugott 'A History of English Syntax' 1972, 82-83"
"Mitchell 'Old English Syntax' 1985 1:pp.789-801"
"Posse 'The Passive in Early Modern English' Atlantis 1993"