Stata Tip 71: The Problem of Split Identity,or How to Group Dyads

Cox N. J. 2002. Speaking Stata: How to move step by: step. Stata Journal 2: 86–102.

Cox N. J. 2007. Stata tip 52: Generating composite categorical variables. Stata Journal 7: 582–583.

Cox N. J. , and Longton G. M. 2008. Speaking Stata: Distinct observations. Stata Journal 8: 557–568.

Herrin J. , and Poen E. 2008. Stata tip 64: Cleaning up user-entered string variables. Stata Journal 8: 444–445.

Kantor D. , and Cox N. J. 2005. Depending on conditions: A tutorial on the cond() function. Stata Journal 5: 413–420.

Kenny D. A. , Kashy D. A. , and Cook W. L. 2006. Dyadic Data Analysis. New York: Guilford Press.