Here's the bio of the book writer:

Sarah Marshall is a writer and journalist who has worked across a variety of celebrity and entertainment magazines including Mizz, Cosmogirl, Bliss, CD-UK and It's Hot! She was editor of a pre-teen title before moving to the BBC magazines Star and Top of the Pops, for which she interviewed many high-profile stars including Justin Timberlake, Britney Spears, Jennifer Ellison and Craig David. Alongside her celebrity writing, Sarah also works for a number of specialist music publications and occasionally contributes to the Evening Standard. Her recent publications include upmarket travel books on Berlin and Lisbon for the Hedonist Guide 2 series. Sarah lives in London.

Is this the same person on Twitter? @SarahMarshall