Hillebrand, H. and U. Sommer. 1996. Nitrogenous nutrition of the potentially toxic diatom Pseudonitzschia pungens f. multiseries Hasle. J. Plankton Res. 18: 295-301.
Hasle, G.R., C.B. Lange, and E.E. Syvertsen. 1996. A review of Pseudo-nitzschia, with special reference to the Skagerrak, North Atlantic, and adjacent waters. Helgoländ. Meeresun. 50: 131-175.
Hasle, G.R. and G.A. Fryxell. 1995. Taxonomy of diatoms, p. 341-366. In: G.M. Hallegraeff, D.M. Anderson, and A.D. Cembella [eds.] IOC manual on harmful marine algae, IOC manuals and guides 33. UNESCO, Paris.