Which of these bibliography citations is preferred?:
Weld, Kirsten. Paper Cadavers: The Archives of Dictatorship in Guatemala. Durham: Duke University Press, 2014.
Weld, Kirsten. Paper Cadavers: The Archives of Dictatorship in Guatemala. Durham: Duke University Press Books, 2014.
Google shows both forms are in use for this particular book (and many like it). In total, Google yields 442,000 results for "Durham: Duke University Press" and 14,200 results for "Durham: Duke University Press Books." Why are there two competing forms?