Cita APA (7a ed.)

Clarke , L. (1997). The essence of chnage. PHI.

Cita Chicago Style (17a ed.)

Clarke , Liz. The Essence of Chnage. New Delhi: PHI, 1997.

Cita MLA (9a ed.)

Clarke , Liz. The Essence of Chnage. PHI, 1997.