Books in the CRYPTIC CASEBOOK OF COCO CARLOMAGNO (AND ALBERTA) series

Buenos Aires' Chief of Police, Coco Carlomagno, is sure his office high in the Obelisco is haunted. There's only one guinea pig Coco can turn to, to help him in his hour of need: his logic-loving cousin Alberta. Can Alberta help him unravel the mysteries of the perplexing pineapple?