The Collected Essays.

These are the last four volumes of the 38 volume set of the only collected works of Britain's most famous 20th century statesman. However, they are often missing from the initial 34 volumes and these four are found in the variant binding of blue, as opposed to cream vellum, one assumes, due to cost.

See appendix to Cohen, Bibliography of the Writings of Sir Winston Churchill, Volume I (pp. 1098-1104): 'the print run never exceeded 2,000 copies and only 1,750 sets were ever published since the publisher was declared bankrupt prior to completing the project. Moreover, it appears that these were only bound as ordered.'