Cita APA (7a ed.)

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

Cita Chicago Style (17a ed.)

Gibson, Joseph, y D. H. Gregory. Carbonisation of Coal. London: Mills & Boon Limited, 1971.

Cita MLA (9a ed.)

Gibson, Joseph, y D. H. Gregory. Carbonisation of Coal. Mills & Boon Limited, 1971.