These are some books written by members of the meetup.
John Myles White
Richard Cotton
Drew Conway & John Myles White
Andrew Gelman & Jeronimo Cortina
Rob Hyndman
Hadley Wickham
Andrew Gelman & Deborah Nolan
Cathy O'Neil & Rachel Schutt
Bryan Lewis and Michael Kane
Q. Ethan McCallum
Harlan Harris, Sean Patrick Murphy & Marck Vaisman
Julia Silge & David Robinson
Wes McKinney
Hadley Wichkam
Max Kuhn
Jared P. Lander
JD Long
JJ Allaire
Andrew Gelman, John B. Carlin, Hal S. Stern, David B. Dunson, Aki Vehtari & Donald B. Rubin
Paul Dix
Max Kuhn & Kjell Johnson
Andrew Gelman
Andrew Gelman & Jennifer Hill
David Robinson
Mike Dewar
Tony Fischetti
Chris Fregly & Antje Barth
Jeroen Janssens
Daniel Y. Chen