When visiting the Chinese city of Shenzen from Hong Kong it is possible to travel on a special Visa called a 'Shenzen Special Economic Zone Tourism Visa'.
The concept is simple. You can quickly get a 5 day visa to visit (only) the area of Shenzen without having to acquire a full China Tourist Visa.
However the conditions for qualifying for this visa change frequently. (one example is that is currently is not available to American or French citizens) A search through the internet yields a lot of advise that is both outdated and inaccurate.
How do I find the official guidelines for this visa? The best I could find was from the Guangdong government, however it doesn't really provide the information required.
(PLEASE note I am not asking what the conditions are, just where I can find the official conditions from the Chinese government)