title: The photoperiodic phenomena: seasonal modulation of the "day within".
authors.affiliation: Hopkins Marine Station, Stanford University, California 94305.
authors.forename: C S
authors.initials: CS
authors.lastname: Pittendrigh
mesh_terms: D006801:Humans; D008027:Light; D010507:Periodicity; D016574:Seasonal Affective Disorder / Q000503:physiopathology; D012621:Seasons