APA (7th ed.) Citation

Gibson, J., & Gregory, D. H. (1971). Carbonisation of coal. Mills and Boon.

Chicago Style (17th ed.) Citation

Gibson, J., and D. H. Gregory. Carbonisation of Coal. London: Mills and Boon, 1971.

MLA (9th ed.) Citation

Gibson, J., and D. H. Gregory. Carbonisation of Coal. Mills and Boon, 1971.