And here, to complete the quartet, is The Veteran Motor Car Pocketbook by Anthony Bird and Francis Hutton-Stott, published in 1963. I bought it in the late '60s, when it cost 9s.6d. (0.475 GBP).
Like the Vintage Pocketbook, it can't pretend to be comprehensive, but covers a reasonable range of manufacturers from AC to Züst. But again, the style of writing is lively and entertaining, and this makes it worth keeping. And the second paragraph of the introduction (shown below), though written some 47 years ago, is as true today as it was then, especially the bit about "completely erroneous information ... printed in perfectly good faith", even though the authors would have had no concept of the internet, Wikipedia, etc.