The Lord of the Rings.
1st Edition, 6th/5th/3rd Imps 1956/57/57.
George Allen & Unwin.
Hardbacks in slipcase.
Hammond p.98.

Not seen.  First state of the slipcase.

Available 1957 to 1958.  Price 63s.

500 sets produced.  Boxed October 1957.

Slipcases manufactured by C. Davidson & Sons.

Covered with grey textured paper ??
Price printed on label.
Three piece construction ??
No staples ??
Uses thinner board than later states ??

Probably includes 1956-57 impressions:

FR 6th Impression 1956
TT 5th Impression 1957
RK 3rd Impression 1957

The 6th Impression 1956 of FR misidentifies itself as the 5th Impression December 1956.