@inbook {650,
	title = {The taxonomic significance of pollen morphology in the Southern African Boraginaceae},
	booktitle = {African plants: Biodiversity, taxonomy and uses},
	year = {1999},
	pages = {319{\textendash}328},
	publisher = {Royal Botanic Gardens},
	organization = {Royal Botanic Gardens},
	address = {Kew},
	author = {Retief, E. and van Wyk, A. E.},
	editor = {Timberlake, J. and Kativu, S.}
}
