1. Chapter 20 A synopsis of Ordovician trilobite distribution and diversity
2. An, T.X., Zhang, F., Xiang, W.D., Zhang, Y.Q., Xu, W.H., Zhang, H.J., Jiang, D.B., Yang, C.S., Lin, L.D., Cui, Z.T. & Yang, X.C., 1983. The Conodonts of North China and the Adjacent Regions. Science Press, Beijing, 223 pp. (Chinese with English abstract)
3. Angelin, N.P., 1851. Palaeontologia Scandinavica. Pars 1. Crustacea Formationis Transitionis Fasc. 2. Norstedt & Söner, Stockholm, 24 pp.