The “DeCasseres Books” were 23 different booklets published between 1936 and 1938.
Those 23 were collected together in 1939 into a three volume set called The Works of Benjamin DeCasseres, and only a small number of copies were made.
In 1975 Gordon Press produced a three volume facsimile edition of The Works of Benjamin DeCasseres in an unknown quantity. I have a set of each, they are very hard to find now.
There was a TWO volume edition made by the printer as a gift to DeCasseres, and maybe 4 copies of those were made? A friend in the UK has that.