British Geological Survey, Hopson, P. M., Aldiss, D. T., & Smith, A. (1996). Geology of the country around Hitchin : memoir for 1:50 000 geological sheet 221 (England and Wales) / P.M. Hopson, D.T. Aldiss, A. Smith: Memoir for 1:50 000 geological sheet 221 (England and Wales). HMSO.
Chicago Style (17th ed.) CitationBritish Geological Survey, P. M. Hopson, D. T. Aldiss, and A. Smith. Geology of the Country Around Hitchin : Memoir for 1:50 000 Geological Sheet 221 (England and Wales) / P.M. Hopson, D.T. Aldiss, A. Smith: Memoir for 1:50 000 Geological Sheet 221 (England and Wales). London: HMSO, 1996.
MLA (9th ed.) CitationBritish Geological Survey, et al. Geology of the Country Around Hitchin : Memoir for 1:50 000 Geological Sheet 221 (England and Wales) / P.M. Hopson, D.T. Aldiss, A. Smith: Memoir for 1:50 000 Geological Sheet 221 (England and Wales). HMSO, 1996.