I am writing a program in Fortran language, in which i use a Random Number Generator (RNG) subroutine. Until now i used ran1 from " Numerical Recipes in fortran ,second edition, Page 271 ", but i think it is quite slow. While searching on the internet for a faster RNG i found a few Fortran subroutines (many were in other languages C/C++ ...), but they were slower than the one i had. Do you know were can i find a fast and quite longperiod (>= 10^12) RNG ???