[[http://www.program-transformation.org/pub/Sts/BlW/a1.html][a1]] [[http://www.program-transformation.org/pub/Sts/BlW/a2.html][a2]] [[http://www.program-transformation.org/pub/Sts/BlW/a3.html][a3]] [[http://www.program-transformation.org/pub/Sts/BlW/a4.html][a4]] [[http://www.program-transformation.org/pub/Sts/BlW/a5.html][a5]] [[http://www.program-transformation.org/pub/Sts/BlW/a6.html][a6]] [[http://www.program-transformation.org/pub/Sts/BlW/a7.html][a7]]