Malvern, D., Richards,Brian J, & Chipere,Ngoni. (2004). Lexical diversity and language development: Quantification and assessment. Palgrave Macmillan.

Malvern, David, Richards,Brian J, and Chipere,Ngoni. Lexical Diversity and Language Development: Quantification and Assessment. Houndmills, Basingstoke, Hampshire ; New York: Palgrave Macmillan, 2004.

Malvern, David, et al. Lexical Diversity and Language Development: Quantification and Assessment. Palgrave Macmillan, 2004.