@article {546,
	title = {Report on the cephalopods of the northeastern coast of America},
	year = {1882},
	month = {1879},
	publisher = {Rep. U.S. Comm. Fish.},
	author = {A.E. Verrill}
}
@article {545,
	title = {Beitr{\"a}ge zur Kenntniss der Pteropoden},
	journal = {Arch. Naturgeschichte},
	volume = {20},
	year = {1854},
	pages = {241},
	chapter = {196},
	author = {F.H. Troschel}
}
@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 {531,
	title = {Contributions to Pteropodernes},
	series = {Morphology of Systematic and for knowledge of their geographical distribution},
	volume = {4},
	year = {1886},
	pages = {1-231},
	publisher = {Spolia Atlantica-Vidensk},
	organization = {Spolia Atlantica-Vidensk},
	edition = {1},
	author = {J.E.V. Boas}
}
@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 {571,
	title = {Die Pteropoden der deutschen S{\"u}dpolar-Expedition 1901-1903},
	journal = {S{\"u}dpol.-Exp. 1901-1903},
	volume = {1},
	year = {1906},
	pages = {153},
	chapter = {92},
	author = {J. Meisenheimer}
}
