1. John N. Bray, John S. Wilson, and Robert A. Wilson, A characterization of finite soluble groups by laws in two variables, Bull. London Math. Soc. 37 (2005), no. 2, 179–186.[MR]
  2. J. B. Wilson, Finding central decompositions of p-groups, J. Group Theory 12 (2009), 813–830.[doi]