It appeared as a British Parliamentary Paper. Most universities and some major metropolitan public libaries have the C19 and C20 sets of BPP on microform (film or fiche) and a very few have them as original printed volumes. Universities are obliged to grant members of the general public access to their holdings (excluding online materials) in return for not paying VAT on their book and journal purchases. So if you're within reach of a university or a major city, make enquiries. For university holdings, copac, an online catalogue of many, though far from all, UK universities' libraries - including microform - is a very useful starting point.