http://www-formal.stanford.edu/jmc/recursive.html http://www-formal.stanford.edu/jmc/recursive.html http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.67

http://www-formal.stanford.edu/jmc/recursive.html http://www-formal.stanford.edu/jmc/recursive.html http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.67.5276&rep=rep1&type=pdf http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.67....