Reetz, M. T., Soni, P., Acevedo, P. P., & Sanchis, J. (2009). Creation of an Amino Acid Network of Structurally Coupled Residues in the Directed Evolution of a Thermostable Enzyme. Angewandte Chemie, 121, 8418-8422. doi:10.1002/ange.200904209.