Heaney, S. (1996). The spirit level (1st pub.). Faber and Faber.
Cita Chicago Style (17a ed.)Heaney, Seamus. The Spirit Level. 1st pub. London [etc.]: Faber and Faber, 1996.
Cita MLA (9a ed.)Heaney, Seamus. The Spirit Level. 1st pub. Faber and Faber, 1996.
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