History of airspace classification/ATC rules etc
 

I have tried this on the ATC forum to no avail, so forgive me if I try here.

Can anyone recommend an online history of airspace classification/ATC rules etc in the UK?

This has been led by trying to find out when the quadrantal rule was introduced for civilian traffic, but there is other stuff I would like to know.

I have looked at the history on the NATS site, but that is much more orientated towards technology and ATC than airspace.

Any other suggestions?

Will