APA (7th ed.) Citation

Clare, J., Tibble, J. W., & Tibble, A. (1951). The letters of John Clare. Routledge & Kegan Paul.

Chicago Style (17th ed.) Citation

Clare, John, J. W. Tibble, and Anne Tibble. The Letters of John Clare. London: Routledge & Kegan Paul, 1951.

MLA (8th ed.) Citation

Clare, John, et al. The Letters of John Clare. Routledge & Kegan Paul, 1951.