Template:Wägele et al., 2006
- Wägele, H.; Vonnemann, V.; Rudman, W.B. 2006: Umbraculum umbraculum (Lightfoot, 1786) (Gastropoda, Opisthobranchia, Tylodinoidea) and the synonymy of U. mediterraneum (Lamarck, 1812). Records of the Western Australian Museum, supplement, (69): 69-82. [not seen]