Hi! I was wondering if anyone had a pdf of Bonaparte, 1991 "Los vertebrados fosiles de la formaciÃn Rio Colorado de Neuquen y cercanias, Cretacico superior, Argentina". Revista del Museo Argentino de Ciencias Naturales "Bernardino Rivadavia" Paleontologia 4 (3): 17-123, where it's described Alvarezsaurus calvoi. Thanks in advance! Josep Fortuny