@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 {542, title = {Das Nervensystem der Heteropoden}, journal = {Z. wiss. Zool.}, volume = {105}, year = {1913}, pages = {279}, chapter = {243}, author = {J.J. Tesch} }