Calvin College's H. Meeter Center for Calvin Studies has acquired a copy of John Calvin's Congrégation faite en l'église de Geneue (Geneva: Vincent Bres, 1562), a true rarity (there are five copies known in Europe and just this one in the U.S.).
The college was recently contacted by a retired theology professor who asked if they'd be interested in the book, which "presents Calvin’s teaching on election, particularly the issue of universal salvation against particular election (Calvin came down on the side of particular election)."
More background on the book and the acquisition here.