I am working in the gravity model using the following article among other references: Anderson, James E., and Eric Van Wincoop. Gravity with gravitas: a solution to the border puzzle. No. w8079. National bureau of economic research, 2001.
The methodology in the article is quite large and time consuming. Other articles have appeared around this topic in order to reduce and simplify the procedure without changing the results. However the article I have mentioned above remain the reference that is the reason I would like to implement it in order to compare the results with mines. However I have heard there exist a do file code to run the methodology presented in the article which it is widely use on internet. I am not able to find the code and I would like to know if someone can help me finding it.