[R] To find how R defined the function of "coxph"?

[Li, Jia]

Dear all,

I am wondering if there is a way to find how R defined(or wrote) the function of 
"coxph"? I don not mean the one that we get by checking help(coxph), but the one 
like coxph<-function(....){...}

Thanks,

Jia