Citazione APA

Heywood, V. H. (1976). Botanical systematics: An occassional series of monographs. Acadamic Press.

Stile di citazione Chicago

Heywood, V H. Botanical Systematics: An Occassional Series of Monographs. London: Acadamic Press, 1976.

Citazione MLA

Heywood, V H. Botanical Systematics: An Occassional Series of Monographs. Acadamic Press, 1976.