@article {669,
	title = {Heliotropium disciforme (Boraginaceae), a new species from northeast Iran},
	journal = {Linzer Biologische Beitr{\"a}ge},
	volume = {23},
	year = {1991},
	pages = {569{\textendash}573},
	author = {Akhani, H.}
}
@article {668,
	title = {Heliotropium esfandiarii (Boraginaceae), a new species from north-central Iran},
	journal = {Linzer Biologische Beitr{\"a}ge},
	volume = {23},
	year = {1991},
	pages = {615{\textendash}620},
	author = {Akhani, H. and Riedl, H.}
}
@inbook {524,
	title = {Boraginaceae},
	booktitle = {Flora of Tropical East Africa},
	volume = {152},
	year = {1991},
	month = {1991///},
	pages = {1 - 124},
	publisher = {Royal Botanic Gardens},
	organization = {Royal Botanic Gardens},
	address = {Kew},
	author = {Verdcourt, B.},
	editor = {Polhill, R. M.}
}
@inbook {492,
	title = {Boraginaceae},
	booktitle = {A revised handbook of the flora of Ceylon},
	year = {1991},
	month = {1991///},
	pages = {3 - 33},
	publisher = {Smithsonian Institution and National Science Foundation},
	organization = {Smithsonian Institution and National Science Foundation},
	address = {Washington, D.C.},
	author = {Nowicke, J. W. and Miller, J. S.},
	editor = {Dassanayake, M. D.}
}
@article {421,
	title = {The genera of Boraginaceae in the southeastern United States},
	journal = {Journal of the Arnold Arboretum Supplementary Series},
	volume = {1},
	year = {1991},
	month = {1991///},
	pages = {1 - 169},
	author = {Al-Shehbaz,I. A.}
}
