Copies of the original Wireless World articles from 1947 and 1949 can be found here 

There's a rather odd American critique of the circuit here http://www.stan-white.com/a_doc_Williamson.htm
Obvious errors in the critique (aside from spelling) include 

    * suggestion that the amplifier hadn't actually been built - the 1949 article makes several suggestions for improvements based on experience of use.  
    * the amplifier relied on a Partridge transformer - Williamson gave construction details for the transformer in the article.  
    * that it is possible to use large (100s of microfarads) smoothing capacitors with a valve rectifier - it certainly wasn't in 1947, and makes little sense even today.

The writer also attributes ideas to Williamson that are patently untrue - Williamson didn't break with convention in using all triodes.  His amplifier was based on the Wireless World quality amplifier, an all triode design from 1934.