1. Daniel Todd Gilbert (USA, b. 1957) who wrote Stumbling on Happiness.
2. Gilbert, Daniel guitarist did write Guitar Soloing : The Contemporary Guide to Improvisation.
3. Dan (Daniel) Gilbert (USA, b. 1979, web developer, a graphic artist, and a cinematographer) wrote Hacking World of Warcraft.
4. Daniel Gilbert, science fiction author of short stories and essays confirmed that he is the same as 1) Daniel Todd Gilbert when he authorized his LT photo. , Bibliography at isfdb.org
5. Daniel Gilbert, photographer - Laos