[1]
P. Lampila, M. Mönkkönen, ja A. Rajasärkkä, ”The ability of forest reserves to maintain original fauna – why has the Chiffchaff (Phylloscopus collybita abietinus) disappeared from eastern central Finland? ”, Ornis Fenn, vsk. 86, nro 2, ss. 71–80, heinä 2009.