Sowerby, G. B. II. (1877). Monograph of the genus Planorbis. In: Conchologia iconica, or illustrations of the shells of molluscous animals, vol. 20: pls 1-14 and unpaginated text. L. Reeve & Co., London. [1877, no month date].
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Sowerby, G. B. II
1877
Monograph of the genus <i>Planorbis</i>. In: <i>Conchologia iconica, or illustrations of the shells of molluscous animals</i>, vol. 20: pls 1-14 and unpaginated text. L. Reeve & Co., London. [1877, no month date]