If it looks like a duck, and quacks like a duck, we have at least to consider the possibility that we have a small aquatic bird of the family Anatidae on our hands.

Douglas Adams (1952-2001) English author, humorist, screenwriter

Dirk Gently No. 1, Dirk Gently’s Holistic Detective Agency, ch. 30 [Dirk] (1987)
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