1. Åqvist, L.: 1965, A New Approach to the Logical Theory of Interrogatives, Almqvist amp; Wiksell, Uppsala.
2. Åqvist, L.: 1969, ‘Scattered topics in interrogative logic’, in: Davis et al. (eds.) [1969], pp. 114–121.
3. Åqvist, L.: 1971, ‘Revised foundations for imperative epistemic and interrogative logic’, Theoria 37, 33–73.
4. Åqvist, L.: 1980, ‘On the “Tell me truly” approach to the analysis of interrogatives’, Unpublished mss. mimeographed, Uppsala.
5. Belnap, N.: 1963, ‘An analysis of questions: preliminary report’, Technical Memorandum 7 1287 1000/00, System Development Corp., Santa Monica, CA.