.
Google with "Puri and Sen (1971) L statistic nonparametric ANCOVA" gives a couple hits:
Puri, M. L. and Sen, P. K. (1969). Analysis of Covariance Based on General Rank Scores, Annals of Mathematical Statistics, 40, No. 2, 610-8.
Puri, M. L. and Sen, P. K. (1971). Nonparametric Methods in Multivariate Analysis, New York, Wiley.
www.jstor.org/stable/2286852
www.jstor.org/stable/2987939
One of the papers characterized it as a generalized rank sum test. Didn't sound like they were endorsing it from the first available page.
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
