@book {575,
	title = {Catalogue of the Mollusca in the collection of the British Museum, 2},
	series = {Pteropoda},
	volume = {4},
	year = {1850},
	pages = {45},
	publisher = {British Museum, E. Newman},
	organization = {British Museum, E. Newman},
	address = {London},
	author = {J.E. Gray}
}
@article {572,
	title = {Pteropoda},
	journal = {Tiefsee Exp. 1898-1899},
	volume = {4},
	year = {1905},
	pages = {314},
	chapter = {1},
	author = {J. Meisenheimer}
}
@book {549,
	title = {Pseudothecosomata, gymnosomata and heteropoda (gastropoda)},
	year = {1976},
	pages = {484},
	publisher = {Bohn, Scheltema \& Holkeme Utrecht},
	organization = {Bohn, Scheltema \& Holkeme Utrecht},
	address = {Amsterdam},
	isbn = {9031301760},
	author = {S. Van Der Spoel}
}
@article {551,
	title = {Variation in Cavolinia longirostris (de Blainville, 1821) from the Pacific Ocean with description of a new form (Mollusca, Pteropoda)},
	journal = {Bull. Zool. Mus.},
	volume = {3},
	year = {1973},
	pages = {102},
	chapter = {99},
	author = {S. Van Der Spoel}
}
