The avocado: botany, production and uses
A. W. Whiley, B. Schaffer, B. N. Wolstenholme · CABI Pub. · 2002
Wikipedia
{{cite book |last=Whiley |first=A. W. |title=The avocado: botany, production and uses |publisher=CABI Pub. |year=2002 |isbn=9780851993577}}