title: Clustering of cases of Hodgkin's disease and leukemia.
mesh_terms: D004739:England; D004812:Epidemiologic Methods; D006689:Hodgkin Disease / Q000453:epidemiology* / Q000635:transmission; D006801:Humans; D007938:Leukemia / Q000453:epidemiology*; D012574:Schools; D013997:Time Factors; D006113:United Kingdom; D014481:United States