Each is first printing, first edition, signed in ink. Poul Anderson book is 4.25x7” paperback “The Rebel World.” Autographed on blank inside cover “To Sterling Lanier-Who Was Instrumental In Bringing Flandry Back Poul Anderson.” ©1969. Trace of lt. cover aging. Inside covers and first and last pages lightly tanned around edges. Fine. Douglas Adams title is 5-1/8x7-1/8” hardcover with dust jacket titled “Life, The Universe And Everything The Cosmic Conclusion To The Hitchhikers Trilogy!” Signed “Douglas Adams” on frontispiece page. Robert Silverberg book is 6-3/8x9-7/8” hardcover with dust jacket titled “Tom O’Bedlam Copyright 1985.” Autographed on right side of title page “For Chris – With Best Wishes – Robert Silverberg.” Dust jackets have tiny trace of dust soil. Exc. Books and autographs are N. Mint. Nice group of famous authors. Comes with Hake's COA.