Siphonophores and velellids: keys and notes for the identification of the species
Kirkpatrick, P.A.; Pugh, P.R. (1984). Siphonophores and velellids: keys and notes for the identification of the species. Synopses of the British Fauna, N.S. 29. E.J. Brill/W. Backhuys: London. ISBN 90-04-07470-8. VI, 154 pp.
Part of: Barnes, R.S.K.; Crothers, J.H. (Ed.) Synopses of the British Fauna. Linnean Society of London: London; New York. ISSN 0082-1101