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2. Deux mais en français?;Anscombre;Lingua,1977
3. Bolinger, D., 1968. The imperative in English. In: To Honor Roman Jakobson. Mouton, Berlin, pp. 335–362.
4. Bolinger, D., 1977. Is the imperative an infinitive? In: Bolinger, D., Meaning and Form. Longman, London, pp. 152–82.
5. Bolkestein, A.M., 1980. Problems in the Description of Modal Verbs. An Investigation of Latin. Van Gorcum, Assen.