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Stereotypic movement disorder can be treated with the use of habit reversal therapy, which was a procedure developed by Azrin and Nunn (1973); this procedure involves teaching the patients to act on competing behaviors when they feel they will engage in a stereotypic behavior . For example, when patients feel like they will begin hand flapping, they will cross their arms instead, thus stopping their stereotypic behavior. Habit reversal has been proven to be successful, effective, and replicable over a span of 25 years. 
^Nolan,Hoeksema, Susan.Abnormal Psychology (6th edition). McGraw Hill, 2013. p.304
See WP:MEDRS on the problem of using outdated sources. You added info sourced to a 1998 review, when the Singer 2009 review (already in the article) more accurately discusses HRT in SMD.
On Wikipedia, we use links to cover info that is better addressed in other articles. I have linked to habit reversal training and removed the redundant info. We don't need to add HOW-TO info on HRT in this article.