Doctor Who: 20 Things You Didn't Know About The Angels Take Manhattan
9. Pond River Publishing
Spoiler alert, but everybody knows that River Song's real name is Melody Pond, and there's a subtle reference to both these monikers in The Angels Take Manhattan.
The book that starts this whole mess – Melody Malone: Private Detective in Old New York Town – is written by River, and published by Amy.
As a result, the name of the publishing company is Pond River Publishing, a neat little nod to both mother and daughter. This detail isn't visible in the episode, but was confirmed by some production artwork.
The actual text inside the book was taken from a real novel called The Thin Man, by Dashiell Hammett.
Hammett was a famous detective writer in the '20s and '30s and was responsible for penning The Maltese Falcon, the film version of which heavily inspired The Angels Take Manhattan's tone and setting.