The Modals in English: a Floating Semantic Feature Analysis

Chomsky, Noam A. 1972. Studies on semantics in generative grammar. The Hague: Mouton.

Ehrman, Madeline E. 1966. The meanings of the modals in present-day American English. The Hague: Mouton & Co.

Hoffman, T. R. 1966. Past tense replacement and the modal system. Harvard computation laboratory report to the National Science Foundation on Mathematical Linguistics and Automatic Translation, NSF - 17. Cambridge, Mass. : Harvard University.

Jenkins, Lyle. 1972. Modality in English syntax. Bloomington, Inc.: Indiana University Linguistics Club.

Joos, Martin. 1966. The English verb. Madison, Wisconsin: The University of Wisconsin Press.

Langendoen, D. Terrence. 1970. Essentials of English grammar. New York: Holt, Rinehart and Winston.

Newmeyer, Frederick J. 1970. The 'root modal': can it be transitive. Studies presented to Robert B. Lees by his students. Edmonton: Linguistic Research, Inc.

Ney, James W. 1974. Two apparent fallacies in current grammatical thought. General linguistics , 14, 4, 182-192.

Palmer, F. R. 1968. A linguistic study of the English verb. Coral Gables, Fla.: University of Miami Press.

Twaddell, W. Freeman. 1960. The English verb auxiliaries. Providence, R.I.: Brown University.