Dear Artur

Thanks for attach.I read this article. It is the best and full of sharp point. But I describe a classification of method and models in molecular clock.

I want an exact number of methods and models. in fact, i am looking for a source that i am referring to that goal(number of method and model ).

I know there are many publications on this subject but i could not find a sourse is clearly mentioned of it.

There really can't be a solid answer for a question like this.  It is similar to asking exactly how many shades of green color exist.  Where do you draw the line between different models and minor modifications of an existing model, for example?  Even with a single model and method, we can slightly change the application such as using more recent, more ancient, or a mix of both, dated samples for calibrating the molecular clock.  For some problems we have very good fossil date/times to use.  For some rapidly evolving viruses we have samples taken over time from the same infected individual, or single transmission chain.  For most molecular clock problems we have only fuzzy estimates of the dates deep in the phylogeny.