Hughes, G. E., & Cresswell, M. J. (1984). A companion to modal logic. Methuen.
Cita Chicago Style (17a ed.)Hughes, G. E., y M. J. Cresswell. A Companion to Modal Logic. London [etc.]: Methuen, 1984.
Cita MLA (9a ed.)Hughes, G. E., y M. J. Cresswell. A Companion to Modal Logic. Methuen, 1984.
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