HADLAND BOOKS
dealing, in part, with Sturmey Archer. Especially noteworthy are the 1954 Master Catalogue pages...  These are high definition zoomable images in Adobe Acrobat format and provide detailed maintenance instructions for many of the classic hubs together with cutaways.

Sturmey Archer's web site

Sheldon Brown's
"Servicing Old 3 Speeds"

Sheldon Brown & Mark Bulgier's
revitalized  "50 years of Sturmey-Archer"
includes a history of the company, and it''s products