There are dozens of the year’s best reference titles, but for sheer labors of love, winners this year are Louisiana Place Names, the entries of which were collected over a lifetime by Clare D’Artois Leeper, who died shortly before this was published by LSU Press, and Flies: The Natural History and Diversity of Diptera from University of Guelph entomologist Stephen A. Marshall, who displays the world’s fly families in 2,200 stunning color photographs from Firefly Books. Find those and many more, including Best Free Reference sources of 2012.