[1]
S. Veistola, E. Lehikoinen, and T. Eeva, “Foraging niches of two passerines at their subarctic limit of distribution: the Siberian Tit Parus cinctus and the Pied Flycatcher Ficedula hypoleuca”, Ornis Fenn, vol. 74, no. 2, pp. 79–87, Jul. 1997.