The first is The Sphinx and the Lotus: the Egyptian movement in American decorative Arts 1865-1935 by Bernadette Sigler and Kevin Stayton. This is the catalog for a 1990 exhibit at the Hudson River Museum in Yonkers, New York and is a slim volume, consisting of several long essays on the subject and an exhibit checklist. This book is well worth picking up at a reasonable price.
Culture and Comfort: People, Parlors and Upholstery 1859-1930, by Katherine Grier is a scholarly examination of upholstery from technical, sociological and cultural standpoints. Originally published in 1989 to coincide with the Strong Museum's exhibit of the same name, it has since been reissued as Culture and Comfort: Parlor Making and Middle-Class Identity, 1850-1930. The reissued version (which I do not own) apparently has been slightly abridged and IIRC lacks the numerous color of the original. Again, I believe this study is unique.
Two other books, which are probably in the realm of "for sad upholstery geeks only" are Upholstery in America and Europe from the Seventeenth Century to World War I: From the Seventeenth Century to World War I, edited by Edward S. Cooke, and Upholstery conservation : preprints of a symposium held at Colonial Williamsburg, February 2-4, 1990, edited by Marc Williams. Both of these books are collections of symposium papers and neither focus solely or even mostly on 19th century upholstery. They are admittedly intended "for the trade"; however, they are great fun if you are the type of