Brisbane Trial:
Buteyko breathing techniques in asthma: a blinded randomized controlled trial Simon D Bowler, Amanda Green and Charles A Mitchell MJA 1998; 169: 575-578

Peter Kolb's site
This site contains asthmatic's experiences with the technique, news stories from around the world and some of the technical information behind the method. 

Buteyko Online
The most comprehensive source of Buteyko on the internet, complete with asthma and treatment resources. It provides you with detailed information you need to understand and control your condition.
This site contains case studies and testimonials from the thousands of people taught by Jennifer and Russell Stark.

Buteyko Institute of Breathing and Health
The Buteyko Institute of Breathing and Health Inc. (BIBH) is the professional association representing the Buteyko Method and Buteyko Practitioners around the world. Formed in 1997, it establishes training standards for Buteyko practitioners and sets standards of ethical and professionally appropriate conduct.