Aglehome Pivot Hinge, Heavy Duty Pivot Door Hardware for Hidden Door Bookcase Hidden Door Hinge for Wood Secret Door 180 Degree Rotation Stainless Steel Invisible Pivot Hinge System - L Shape :
DIY Hidden Bookcase Door / Secret Door Pivot Hinge Kit H-KIT - Etsy UK
Bookcase Doors
DIY Hidden Doorway Bookcase - Bright Green Door
Hidden Library/Bookcase Door Open - Asian - Home Office - San Francisco - by User | Houzz UK
Made a hidden bookshelf-door and the opening mechanism is disguised as a book! What do you think about that? I can't upload more then one image sadly. Videodescription is in the comments.
Make a Bookshelf Door Hidden Closet - The Geek Pub