Pharrell Williams to release digital book

London: Grammy award-winning rapper Pharrell Williams has surprised fans by announcing he will release a new digital book online.

Just hours after the `Happy` hitmaker released the music video for his new single `Marilyn Monroe`, Williams also revealed that he is releasing a new, untitled book, reportedly.

He has not provided many details, but took to Twitter and wrote, "Happy... Just finished my new book. You can only read it online. I`ll tweet the link on Thursday. Hope you enjoy."

This is not the 41-year-old singer`s first venture into publishing, he released `Pharrell: Places and Spaces I`ve Been` last October.