Wim Hof's technique is a bastardized western version of pranayama (as are the other 'recommended' books here) go for the original http://www.yogebooks.com/engl

Wim Hof's technique is a bastardized western version of pranayama (as are the other 'recommended' books here) go for the original http://www.yogebooks.com/english/atkinson/1903sciencebreath.pdf http://www.yogebooks.com/english/atkinson/1903sciencebreath....