APA

Calder D. R., Mallinson J. J., Collins K. & Hickman C. P. (2003). Additions to the hydroids (Cnidaria) of the Galápagos, with a list of species reported from the islands. : .

Chicago

Calder D R, Mallinson J J, Collins K and Hickman C P. 2003. Additions to the hydroids (Cnidaria) of the Galápagos, with a list of species reported from the islands. : .

Harvard

Calder D. R., Mallinson J. J., Collins K. and Hickman C. P. (2003). Additions to the hydroids (Cnidaria) of the Galápagos, with a list of species reported from the islands. : .

MLA

Calder D R, Mallinson J J, Collins K and Hickman C P. Additions to the hydroids (Cnidaria) of the Galápagos, with a list of species reported from the islands. : . 2003.