Winter to spring transition and diurnal variation of VOCs in Finland at an urban background site and a rural site - Patokoski, Johanna; Ruuskanen, Taina M.; Hellén, Heidi; Taipale, Risto; Grönholm, Tiia; Kajos, Maija K.; Petäjä, Tuukka; Hakola, Hannele; Kulmala, Markku; Rinne, Janne (Boreal Environment Research Publishing Board, 2017)