title: Why is the sky blue?
authors.affiliation: Johns Hopkins Health Care, Baltimore, MD 21287-0764, USA.
authors.forename: J D
authors.initials: JD
authors.lastname: Stobo
mesh_terms: D005106:Exploratory Behavior; D006801:Humans; D015272:Pulmonary Medicine / Q000639:trends*; D012106:Research / Q000639:trends