This is a paid asset, but now you can download 3D Book System Free.
Detail this asset from Unity Store: Original Link
3D Book System v1.2 (Latest version)
– Multiple control systems included for keyboard, mouse clicks, and swipes.
– Multiple examples including a low poly 3D book with animated pages, a non-animated cardboard book, and a vertically aligned notepad style 3D book.
– Low poly book, pages, and cardboard pieces in .fbx format.
– Textures are 1024 x 1024 and 512 x 512 layered .psd files complete with model UVs for retexturing.
– Scripts written in a self-documenting style in C# with additional comments throughout.
Try the WebGL version here.