@article {536,
	title = {Descriptions of sixty new forms of mollusks from the west coast of North America and the north Pacific Ocean, with notes on others already described},
	journal = {American J. Conch},
	volume = {7},
	year = {1871},
	pages = {160},
	chapter = {93},
	author = {W.H. Dall}
}
@article {572,
	title = {Pteropoda},
	journal = {Tiefsee Exp. 1898-1899},
	volume = {4},
	year = {1905},
	pages = {314},
	chapter = {1},
	author = {J. Meisenheimer}
}
@article {541,
	title = {Vorl{\"a}ufige Mitteilung {\"u}ber die Thecosomata und Gymnosomata der Siboga-Expedition},
	journal = {Tijdsch. Nederl. Dierk.},
	volume = {2},
	year = {1903},
	pages = {117},
	chapter = {111},
	author = {J.J. Tesch}
}
@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 {532,
	title = {Pteropoda from the Michael Sars North-Atlantic Deep-Sea expedition},
	journal = {{\textquoteright}Michael Sars{\textquoteright} North Atl},
	volume = {3},
	year = {1913},
	month = {1933},
	pages = {69},
	chapter = {1},
	author = {K. Bonnevie}
}
