By Howard R. Lemcke. Previously published as Death in a Fishpond; wise choice to update it, IMO. Also: "With evidence pointing to a tragic accident, and David [Mead] the model of a bereaved widower, the case was ready to be closed" could be fully two thirds of the Dateline catalog, no?
This paperback is ready to be opened -- by you! ...I'm sorry. It is in decent shape, though: mild corner- and edgewear; a cracked spine with a slight lean; inside, clean with no dog-ears. Fine reading copy.