C. Nielsen

Systematics: Sequences lead to tree of worms

C. Nielsen, Claus Nielsen, 1998, Nature.

Xenoturbella is a deuterostome that eats molluscs

Sarah J. Bourlat, M. Telford, D. Littlewood, 2003, Nature.

Testing the new animal phylogeny: a phylum level molecular analysis of the animal kingdom.

Sarah J. Bourlat, Maximilian J Telford, M. Telford, 2008, Molecular phylogenetics and evolution.

CLADISTIC ANALYSES OF THE ANIMAL KINGDOM

N. Scharff, C. Nielsen, D. Eibye‐Jacobsen, 1996 .

Origin and evolution of animal life cycles

C. Nielsen, 1998 .

Morphological Approaches to Phylogeny

C. Nielsen, 1998 .

The phylogenetic position of the Arthropoda

C. Nielsen, 1998 .

Studies on Enchytraeidae IV

B. Christensen, Bent Christensen, C. Overgaard Nielsen, 2004, Chromosoma.

A review of the solitary entoprocts reported from sponges from Napoli (Italy), with designation of a neotype of Loxosoma pes Schmidt, 1878

C. Nielsen, 2008 .