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Van Soest, R.W.M.; Hooper, J.N.A. (2002). Order Spirophorida Bergquist & Hogg, 1969. Pp. 83-84. In: Hooper, J.N.A. & Van Soest, R.W.M. (eds) Systema Porifera. A guide to the classification of sponges. 2 volumes. Kluwer Academic / Plenum Publishers: New York, 1708 + xlviii. ISBN 0-306-47260-0 (printed version).