What are Predictive Clustering Trees in machine learning? Anybody could let me know what exactly the PDT is and where does it come from? it comes from predictive modeling or decision tress?

I read some articles and websites like: this and this
but both of them are about predictive modeling. I think PDT comes from decision tree rather than predictive modeling.
Clus might get you started. It uses predictive clustering trees and is described in this article, although you'll probably need a student account to get access to that article.

They have a list of publications that you should also find instructive.