Bilaterians
Eukaryotes
Douzery, EJP, EA Snell, E Bapteste, F Delsuc, H Philippe. 2004. The timing of eukaryotic evolution: Does a relaxed molecular clock reconcile proteins and fossils? Proceedings of the National Academy of Sciences of the United States of America 43:15386-15391.

Bilaterians
Erwin DH, et al. (2011)
The Cambrian Conundrum: Early Divergence and Later Ecological Success in the Early History of Animals. Science 334(6059):1091-1097.

Peterson, K. J., J. A. Cotton, J. G. Gehling, and D. Pisani. 2008.
The Ediacaran emergence of bilaterians: congruence between the genetic and the geological fossil records. Philosophical Transactions of the Royal Society B-Biological Sciences 363:1435-1443.

Protostomes
Tamura, K., S. Subramanian, and S. Kumar. 2004.

Drosophila
Tamura, K., S. Subramanian, and S. Kumar. 2004.
Temporal patterns of fruit fly (Drosophila) evolution revealed by mutation clocks.
Mol Biol Evol:36-44.

Wiegmann, B. M., D. K. Yeates, J. L. Thorne, and H. Kishino. 2003.
Time flies, a new molecular time-scale for brachyceran fly evolution without a clock.
Syst. Biol. 52:745-756.